fixup deps

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

.gitea/pkgdashcli.yaml

@@ -1,3 +0,0 @@
-branches:
-  - master
-  - v3

.gitea/workflows/autoupdate.yml

@@ -1,24 +0,0 @@
-on:
-  push:
-    branches:
-    - 'main'
-    - 'master'
-    - 'v3'
-  schedule:
-    #- cron: '* * * * *'
-    - cron: '@hourly'
-
-jobs:
-  autoupdate:
-    runs-on: ubuntu-latest
-    steps:
-    - name: setup-go
-      uses: https://gitea.com/actions/setup-go@v3
-      with:
-        go-version: 1.21
-    - name: checkout
-      uses: https://gitea.com/actions/checkout@v3
-    - name: get pkgdashcli
-      run: GOPROXY=direct GONOSUMDB="git.unistack.org/*" GONOPROXY="git.unistack.org/*" GOBIN=/bin go install git.unistack.org/unistack-org/pkgdash/cmd/pkgdashcli@latest
-    - name: pkgdashcli check
-      run: /bin/pkgdashcli check

.gitea/workflows/coverage.yml

@@ -1,30 +0,0 @@
-name: Go
-
-on:
-  push:
-    branches: [ master, v3 ]
-  pull_request:
-    branches: [ master, v3 ]
-  workflow_dispatch:
-
-jobs:
-  test:
-    runs-on: ubuntu-latest
-    steps:
-    - name: checkout
-      uses: actions/checkout@v4
-
-    - name: setup
-      uses: actions/setup-go@v4
-      with:
-        go-version: stable
-
-    - name: coverage
-      run: go test -v -coverprofile coverage.out ./...
-
-    - name: badge
-      uses: ncruces/go-coverage-report@main
-      with:
-        coverage-file: coverage.out
-        reuse-go: true
-        amend: true

.gitea/workflows/lint.yml

@@ -10,15 +10,15 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: setup-go
-      uses: https://gitea.com/actions/setup-go@v3
+      uses: actions/setup-go@v3
       with:
         go-version: 1.21
     - name: checkout
-      uses: https://gitea.com/actions/checkout@v3
+      uses: actions/checkout@v3
     - name: deps
       run: go get -v -d ./...
     - name: lint
       uses: https://github.com/golangci/golangci-lint-action@v3.4.0
       continue-on-error: true
       with:
-        version: v1.52
+        version: v1.52

.gitea/workflows/pr.yml

@@ -10,9 +10,9 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: checkout
-      uses: https://gitea.com/actions/checkout@v3
+      uses: actions/checkout@v3
     - name: setup-go
-      uses: https://gitea.com/actions/setup-go@v3
+      uses: actions/setup-go@v3
       with:
         go-version: 1.21
     - name: deps
@@ -20,4 +20,4 @@ jobs:
     - name: test
       env:
         INTEGRATION_TESTS: yes
-      run: go test -v -mod readonly -race -coverprofile=coverage.txt -covermode=atomic ./...
+      run: go test -mod readonly -v ./...

.gitignore

@@ -1,8 +1,6 @@
 # Develop tools
 /.vscode/
 /.idea/
-.idea
-.vscode
 
 # Binaries for programs and plugins
 *.exe
@@ -15,7 +13,6 @@
 _obj
 _test
 _build
-.DS_Store
 
 # Architecture specific extensions/prefixes
 *.[568vq]

.golangci.yml

@@ -1,5 +1,6 @@
 run:
   concurrency: 4
+  deadline: 5m
   issues-exit-code: 1
   tests: true
 
@@ -12,13 +13,15 @@ linters-settings:
 linters:
   enable:
     - govet
+    - deadcode
     - errcheck
     - govet
     - ineffassign
     - staticcheck
+    - structcheck
     - typecheck
     - unused
-    - spancheck
+    - varcheck
     - bodyclose
     - gci
     - goconst
@@ -38,5 +41,4 @@ linters:
     - prealloc
     - unconvert
     - unparam
-    - unused
   disable-all: false

README.md

@@ -1,4 +1,4 @@
-# Micro [![License](https://img.shields.io/:license-apache-blue.svg)](https://opensource.org/licenses/Apache-2.0) [![Doc](https://img.shields.io/badge/go.dev-reference-007d9c?logo=go&logoColor=white&style=flat-square)](https://pkg.go.dev/go.unistack.org/micro/v4?tab=overview) [![Status](https://github.com/unistack-org/micro/workflows/build/badge.svg?branch=master)](https://github.com/unistack-org/micro/actions?query=workflow%3Abuild+branch%3Amaster+event%3Apush) [![Lint](https://goreportcard.com/badge/go.unistack.org/micro/v4)](https://goreportcard.com/report/go.unistack.org/micro/v4) [![Coverage](https://codecov.io/gh/unistack-org/micro/branch/v4/graph/badge.svg?token=OZPO2LP7VS)](https://codecov.io/gh/unistack-org/micro)
+# Micro [![License](https://img.shields.io/:license-apache-blue.svg)](https://opensource.org/licenses/Apache-2.0) [![Doc](https://img.shields.io/badge/go.dev-reference-007d9c?logo=go&logoColor=white&style=flat-square)](https://pkg.go.dev/github.com/unistack-org/micro/v3?tab=overview) [![Status](https://github.com/unistack-org/micro/workflows/build/badge.svg?branch=master)](https://github.com/unistack-org/micro/actions?query=workflow%3Abuild+branch%3Amaster+event%3Apush) [![Lint](https://goreportcard.com/badge/go.unistack.org/micro/v3)](https://goreportcard.com/report/go.unistack.org/micro/v3) [![Coverage](https://codecov.io/gh/unistack-org/micro/branch/v3/graph/badge.svg?token=OZPO2LP7VS)](https://codecov.io/gh/unistack-org/micro)
 
 Micro is a standard library for microservices.
 

broker/broker.go

@@ -1,27 +1,22 @@
 // Package broker is an interface used for asynchronous messaging
-package broker // import "go.unistack.org/micro/v4/broker"
+package broker // import "go.unistack.org/micro/v3/broker"
 
 import (
 	"context"
 	"errors"
-	"time"
 
-	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v4/options"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/metadata"
 )
 
 // DefaultBroker default memory broker
-var DefaultBroker Broker = NewBroker()
+var DefaultBroker = NewBroker()
 
 var (
 	// ErrNotConnected returns when broker used but not connected yet
 	ErrNotConnected = errors.New("broker not connected")
 	// ErrDisconnected returns when broker disconnected
 	ErrDisconnected = errors.New("broker disconnected")
-	// ErrInvalidMessage returns when message has nvalid format
-	ErrInvalidMessage = errors.New("broker message has invalid format")
-	// DefaultGracefulTimeout
-	DefaultGracefulTimeout = 5 * time.Second
 )
 
 // Broker is an interface used for asynchronous messaging.
@@ -29,7 +24,7 @@ type Broker interface {
 	// Name returns broker instance name
 	Name() string
 	// Init initilize broker
-	Init(opts ...options.Option) error
+	Init(opts ...Option) error
 	// Options returns broker options
 	Options() Options
 	// Address return configured address
@@ -38,29 +33,72 @@ type Broker interface {
 	Connect(ctx context.Context) error
 	// Disconnect disconnect from broker
 	Disconnect(ctx context.Context) error
-	// Publish message, msg can be single broker.Message or []broker.Message
-	Publish(ctx context.Context, msg interface{}, opts ...options.Option) error
+	// Publish message to broker topic
+	Publish(ctx context.Context, topic string, msg *Message, opts ...PublishOption) error
 	// Subscribe subscribes to topic message via handler
-	Subscribe(ctx context.Context, topic string, handler interface{}, opts ...options.Option) (Subscriber, error)
+	Subscribe(ctx context.Context, topic string, h Handler, opts ...SubscribeOption) (Subscriber, error)
+	// BatchPublish messages to broker with multiple topics
+	BatchPublish(ctx context.Context, msgs []*Message, opts ...PublishOption) error
+	// BatchSubscribe subscribes to topic messages via handler
+	BatchSubscribe(ctx context.Context, topic string, h BatchHandler, opts ...SubscribeOption) (Subscriber, error)
 	// String type of broker
 	String() string
 }
 
-// Message is given to a subscription handler for processing
-type Message interface {
-	// Context for the message
-	Context() context.Context
-	// Topic
+// Handler is used to process messages via a subscription of a topic.
+type Handler func(Event) error
+
+// Events contains multiple events
+type Events []Event
+
+// Ack try to ack all events and return
+func (evs Events) Ack() error {
+	var err error
+	for _, ev := range evs {
+		if err = ev.Ack(); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// SetError sets error on event
+func (evs Events) SetError(err error) {
+	for _, ev := range evs {
+		ev.SetError(err)
+	}
+}
+
+// BatchHandler is used to process messages in batches via a subscription of a topic.
+type BatchHandler func(Events) error
+
+// Event is given to a subscription handler for processing
+type Event interface {
+	// Topic returns event topic
 	Topic() string
-	// Header returns message headers
-	Header() metadata.Metadata
-	// Body returns broker message may be []byte slice or some go struct
-	Body() interface{}
+	// Message returns broker message
+	Message() *Message
 	// Ack acknowledge message
 	Ack() error
 	// Error returns message error (like decoding errors or some other)
-	// In this case Body contains raw []byte from broker
 	Error() error
+	// SetError set event processing error
+	SetError(err error)
+}
+
+// Message is used to transfer data
+type Message struct {
+	// Header contains message metadata
+	Header metadata.Metadata
+	// Body contains message body
+	Body codec.RawMessage
+}
+
+// NewMessage create broker message with topic filled
+func NewMessage(topic string) *Message {
+	m := &Message{Header: metadata.New(2)}
+	m.Header.Set(metadata.HeaderTopic, topic)
+	return m
 }
 
 // Subscriber is a convenience return type for the Subscribe method
@@ -72,9 +110,3 @@ type Subscriber interface {
 	// Unsubscribe from topic
 	Unsubscribe(ctx context.Context) error
 }
-
-// MessageHandler func signature for single message processing
-type MessageHandler func(Message) error
-
-// MessagesHandler func signature for batch message processing
-type MessagesHandler func([]Message) error

broker/context.go

@@ -22,3 +22,33 @@ func NewContext(ctx context.Context, s Broker) context.Context {
 	}
 	return context.WithValue(ctx, brokerKey{}, s)
 }
+
+// SetSubscribeOption returns a function to setup a context with given value
+func SetSubscribeOption(k, v interface{}) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}
+
+// SetOption returns a function to setup a context with given value
+func SetOption(k, v interface{}) Option {
+	return func(o *Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}
+
+// SetPublishOption returns a function to setup a context with given value
+func SetPublishOption(k, v interface{}) PublishOption {
+	return func(o *PublishOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}

broker/context_test.go

@@ -37,3 +37,36 @@ func TestNewNilContext(t *testing.T) {
 		t.Fatal("NewContext not works")
 	}
 }
+
+func TestSetSubscribeOption(t *testing.T) {
+	type key struct{}
+	o := SetSubscribeOption(key{}, "test")
+	opts := &SubscribeOptions{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetSubscribeOption not works")
+	}
+}
+
+func TestSetPublishOption(t *testing.T) {
+	type key struct{}
+	o := SetPublishOption(key{}, "test")
+	opts := &PublishOptions{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetPublishOption not works")
+	}
+}
+
+func TestSetOption(t *testing.T) {
+	type key struct{}
+	o := SetOption(key{}, "test")
+	opts := &Options{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetOption not works")
+	}
+}

broker/memory.go

@@ -1,334 +0,0 @@
-package broker
-
-import (
-	"context"
-	"fmt"
-	"sync"
-	"time"
-
-	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v4/semconv"
-	maddr "go.unistack.org/micro/v4/util/addr"
-	"go.unistack.org/micro/v4/util/id"
-	mnet "go.unistack.org/micro/v4/util/net"
-	"go.unistack.org/micro/v4/util/rand"
-)
-
-type MemoryBroker struct {
-	subscribers map[string][]*memorySubscriber
-	addr        string
-	opts        Options
-	sync.RWMutex
-	connected bool
-}
-
-func (m *MemoryBroker) Options() Options {
-	return m.opts
-}
-
-func (m *MemoryBroker) Address() string {
-	return m.addr
-}
-
-func (m *MemoryBroker) Connect(ctx context.Context) error {
-	m.Lock()
-	defer m.Unlock()
-
-	if m.connected {
-		return nil
-	}
-
-	// use 127.0.0.1 to avoid scan of all network interfaces
-	addr, err := maddr.Extract("127.0.0.1")
-	if err != nil {
-		return err
-	}
-	var rng rand.Rand
-	i := rng.Intn(20000)
-	// set addr with port
-	addr = mnet.HostPort(addr, 10000+i)
-
-	m.addr = addr
-	m.connected = true
-
-	return nil
-}
-
-func (m *MemoryBroker) Disconnect(ctx context.Context) error {
-	m.Lock()
-	defer m.Unlock()
-
-	select {
-	case <-ctx.Done():
-		return ctx.Err()
-	default:
-		if m.connected {
-			m.connected = false
-		}
-	}
-
-	return nil
-}
-
-func (m *MemoryBroker) Init(opts ...options.Option) error {
-	var err error
-	for _, o := range opts {
-		if err = o(&m.opts); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-func (m *MemoryBroker) Publish(ctx context.Context, message interface{}, opts ...options.Option) error {
-	m.RLock()
-	if !m.connected {
-		m.RUnlock()
-		return ErrNotConnected
-	}
-	m.RUnlock()
-
-	var err error
-
-	select {
-	case <-ctx.Done():
-		return ctx.Err()
-	default:
-		options := NewPublishOptions(opts...)
-		var msgs []Message
-		switch v := message.(type) {
-		case []Message:
-			msgs = v
-		case Message:
-			msgs = append(msgs, v)
-		default:
-			return ErrInvalidMessage
-		}
-		msgTopicMap := make(map[string][]*memoryMessage)
-		for _, msg := range msgs {
-			p := &memoryMessage{opts: options}
-			p.topic, _ = msg.Header().Get(metadata.HeaderTopic)
-			if v, ok := msg.Body().(*codec.Frame); ok {
-				p.body = msg.Body()
-			} else if len(m.opts.Codecs) == 0 {
-				p.body = msg.Body()
-			} else {
-				cf, ok := m.opts.Codecs[options.ContentType]
-				if !ok {
-					return fmt.Errorf("%s: %s", codec.ErrUnknownContentType, options.ContentType)
-				}
-				p.body, err = cf.Marshal(v)
-				if err != nil {
-					return err
-				}
-			}
-			msgTopicMap[p.topic] = append(msgTopicMap[p.topic], p)
-		}
-
-		eh := m.opts.ErrorHandler
-
-		for t, ms := range msgTopicMap {
-			ts := time.Now()
-
-			m.opts.Meter.Counter(semconv.PublishMessageInflight, "endpoint", t).Add(len(ms))
-			m.opts.Meter.Counter(semconv.SubscribeMessageInflight, "endpoint", t).Add(len(ms))
-
-			m.RLock()
-			subs, ok := m.subscribers[t]
-			m.RUnlock()
-			if !ok {
-				m.opts.Meter.Counter(semconv.PublishMessageTotal, "endpoint", t, "status", "failure").Add(len(ms))
-				m.opts.Meter.Counter(semconv.PublishMessageInflight, "endpoint", t).Add(-len(ms))
-				m.opts.Meter.Counter(semconv.SubscribeMessageInflight, "endpoint", t).Add(-len(ms))
-				continue
-			}
-
-			m.opts.Meter.Counter(semconv.PublishMessageTotal, "endpoint", t, "status", "success").Add(len(ms))
-			for _, sub := range subs {
-				if sub.opts.ErrorHandler != nil {
-					eh = sub.opts.ErrorHandler
-				}
-
-				switch mh := sub.handler.(type) {
-				case MessagesHandler:
-					mhs := make([]Message, 0, len(ms))
-					for _, m := range ms {
-						mhs = append(mhs, m)
-					}
-					if err = mh(mhs); err != nil {
-						m.opts.Meter.Counter(semconv.SubscribeMessageTotal, "endpoint", t, "status", "failure").Add(len(ms))
-						if eh != nil {
-							switch meh := eh.(type) {
-							case MessagesHandler:
-								_ = meh(mhs)
-							case MessageHandler:
-								for _, me := range mhs {
-									_ = meh(me)
-								}
-							}
-						} else if m.opts.Logger.V(logger.ErrorLevel) {
-							m.opts.Logger.Error(m.opts.Context, err.Error())
-						}
-					}
-				case MessageHandler:
-					for _, p := range ms {
-						if err = mh(p); err != nil {
-							m.opts.Meter.Counter(semconv.SubscribeMessageTotal, "endpoint", t, "status", "failure").Inc()
-							if eh != nil {
-								switch meh := eh.(type) {
-								case MessageHandler:
-									_ = meh(p)
-								case MessagesHandler:
-									_ = meh([]Message{p})
-								}
-							} else if m.opts.Logger.V(logger.ErrorLevel) {
-								m.opts.Logger.Error(m.opts.Context, err.Error())
-							}
-						} else {
-							if sub.opts.AutoAck {
-								if err = p.Ack(); err != nil {
-									m.opts.Logger.Error(m.opts.Context, "ack failed: "+err.Error())
-									m.opts.Meter.Counter(semconv.SubscribeMessageTotal, "endpoint", t, "status", "failure").Inc()
-								} else {
-									m.opts.Meter.Counter(semconv.SubscribeMessageTotal, "endpoint", t, "status", "success").Inc()
-								}
-							} else {
-								m.opts.Meter.Counter(semconv.SubscribeMessageTotal, "endpoint", t, "status", "success").Inc()
-							}
-						}
-						m.opts.Meter.Counter(semconv.PublishMessageInflight, "endpoint", t).Add(-1)
-						m.opts.Meter.Counter(semconv.SubscribeMessageInflight, "endpoint", t).Add(-1)
-					}
-				}
-			}
-
-			te := time.Since(ts)
-			m.opts.Meter.Summary(semconv.PublishMessageLatencyMicroseconds, "endpoint", t).Update(te.Seconds())
-			m.opts.Meter.Histogram(semconv.PublishMessageDurationSeconds, "endpoint", t).Update(te.Seconds())
-			m.opts.Meter.Summary(semconv.SubscribeMessageLatencyMicroseconds, "endpoint", t).Update(te.Seconds())
-			m.opts.Meter.Histogram(semconv.SubscribeMessageDurationSeconds, "endpoint", t).Update(te.Seconds())
-		}
-
-	}
-
-	return nil
-}
-
-func (m *MemoryBroker) Subscribe(ctx context.Context, topic string, handler interface{}, opts ...options.Option) (Subscriber, error) {
-	m.RLock()
-	if !m.connected {
-		m.RUnlock()
-		return nil, ErrNotConnected
-	}
-	m.RUnlock()
-
-	sid, err := id.New()
-	if err != nil {
-		return nil, err
-	}
-
-	options := NewSubscribeOptions(opts...)
-
-	sub := &memorySubscriber{
-		exit:    make(chan bool, 1),
-		id:      sid,
-		topic:   topic,
-		handler: handler,
-		opts:    options,
-		ctx:     ctx,
-	}
-
-	m.Lock()
-	m.subscribers[topic] = append(m.subscribers[topic], sub)
-	m.Unlock()
-
-	go func() {
-		<-sub.exit
-		m.Lock()
-		newSubscribers := make([]*memorySubscriber, 0, len(m.subscribers)-1)
-		for _, sb := range m.subscribers[topic] {
-			if sb.id == sub.id {
-				continue
-			}
-			newSubscribers = append(newSubscribers, sb)
-		}
-		m.subscribers[topic] = newSubscribers
-		m.Unlock()
-	}()
-
-	return sub, nil
-}
-
-func (m *MemoryBroker) String() string {
-	return "memory"
-}
-
-func (m *MemoryBroker) Name() string {
-	return m.opts.Name
-}
-
-type memoryMessage struct {
-	err    error
-	body   interface{}
-	topic  string
-	header metadata.Metadata
-	opts   PublishOptions
-	ctx    context.Context
-}
-
-func (m *memoryMessage) Topic() string {
-	return m.topic
-}
-
-func (m *memoryMessage) Header() metadata.Metadata {
-	return m.header
-}
-
-func (m *memoryMessage) Body() interface{} {
-	return m.body
-}
-
-func (m *memoryMessage) Ack() error {
-	return nil
-}
-
-func (m *memoryMessage) Error() error {
-	return m.err
-}
-
-func (m *memoryMessage) Context() context.Context {
-	return m.ctx
-}
-
-type memorySubscriber struct {
-	ctx     context.Context
-	exit    chan bool
-	handler interface{}
-	id      string
-	topic   string
-	opts    SubscribeOptions
-}
-
-func (m *memorySubscriber) Options() SubscribeOptions {
-	return m.opts
-}
-
-func (m *memorySubscriber) Topic() string {
-	return m.topic
-}
-
-func (m *memorySubscriber) Unsubscribe(ctx context.Context) error {
-	m.exit <- true
-	return nil
-}
-
-// NewBroker return new memory broker
-func NewBroker(opts ...options.Option) *MemoryBroker {
-	return &MemoryBroker{
-		opts:        NewOptions(opts...),
-		subscribers: make(map[string][]*memorySubscriber),
-	}
-}

broker/memory/memory.go

@@ -0,0 +1,355 @@
+package broker
+
+import (
+	"context"
+	"sync"
+
+	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/metadata"
+	maddr "go.unistack.org/micro/v3/util/addr"
+	"go.unistack.org/micro/v3/util/id"
+	mnet "go.unistack.org/micro/v3/util/net"
+	"go.unistack.org/micro/v3/util/rand"
+)
+
+type memoryBroker struct {
+	subscribers map[string][]*memorySubscriber
+	addr        string
+	opts        broker.Options
+	sync.RWMutex
+	connected bool
+}
+
+type memoryEvent struct {
+	err     error
+	message interface{}
+	topic   string
+	opts    broker.Options
+}
+
+type memorySubscriber struct {
+	ctx          context.Context
+	exit         chan bool
+	handler      broker.Handler
+	batchhandler broker.BatchHandler
+	id           string
+	topic        string
+	opts         broker.SubscribeOptions
+}
+
+func (m *memoryBroker) Options() broker.Options {
+	return m.opts
+}
+
+func (m *memoryBroker) Address() string {
+	return m.addr
+}
+
+func (m *memoryBroker) Connect(ctx context.Context) error {
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	default:
+	}
+
+	m.Lock()
+	defer m.Unlock()
+
+	if m.connected {
+		return nil
+	}
+
+	// use 127.0.0.1 to avoid scan of all network interfaces
+	addr, err := maddr.Extract("127.0.0.1")
+	if err != nil {
+		return err
+	}
+	var rng rand.Rand
+	i := rng.Intn(20000)
+	// set addr with port
+	addr = mnet.HostPort(addr, 10000+i)
+
+	m.addr = addr
+	m.connected = true
+
+	return nil
+}
+
+func (m *memoryBroker) Disconnect(ctx context.Context) error {
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	default:
+	}
+
+	m.Lock()
+	defer m.Unlock()
+
+	if !m.connected {
+		return nil
+	}
+
+	m.connected = false
+	return nil
+}
+
+func (m *memoryBroker) Init(opts ...broker.Option) error {
+	for _, o := range opts {
+		o(&m.opts)
+	}
+	return nil
+}
+
+func (m *memoryBroker) Publish(ctx context.Context, topic string, msg *broker.Message, opts ...broker.PublishOption) error {
+	msg.Header.Set(metadata.HeaderTopic, topic)
+	return m.publish(ctx, []*broker.Message{msg}, opts...)
+}
+
+func (m *memoryBroker) BatchPublish(ctx context.Context, msgs []*broker.Message, opts ...broker.PublishOption) error {
+	return m.publish(ctx, msgs, opts...)
+}
+
+func (m *memoryBroker) publish(ctx context.Context, msgs []*broker.Message, opts ...broker.PublishOption) error {
+	m.RLock()
+	if !m.connected {
+		m.RUnlock()
+		return broker.ErrNotConnected
+	}
+	m.RUnlock()
+
+	var err error
+
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	default:
+		options := broker.NewPublishOptions(opts...)
+
+		msgTopicMap := make(map[string]broker.Events)
+		for _, v := range msgs {
+			p := &memoryEvent{opts: m.opts}
+
+			if m.opts.Codec == nil || options.BodyOnly {
+				p.topic, _ = v.Header.Get(metadata.HeaderTopic)
+				p.message = v.Body
+			} else {
+				p.topic, _ = v.Header.Get(metadata.HeaderTopic)
+				p.message, err = m.opts.Codec.Marshal(v)
+				if err != nil {
+					return err
+				}
+			}
+			msgTopicMap[p.topic] = append(msgTopicMap[p.topic], p)
+		}
+
+		beh := m.opts.BatchErrorHandler
+		eh := m.opts.ErrorHandler
+
+		for t, ms := range msgTopicMap {
+			m.RLock()
+			subs, ok := m.subscribers[t]
+			m.RUnlock()
+			if !ok {
+				continue
+			}
+
+			for _, sub := range subs {
+				if sub.opts.BatchErrorHandler != nil {
+					beh = sub.opts.BatchErrorHandler
+				}
+				if sub.opts.ErrorHandler != nil {
+					eh = sub.opts.ErrorHandler
+				}
+
+				switch {
+				// batch processing
+				case sub.batchhandler != nil:
+					if err = sub.batchhandler(ms); err != nil {
+						ms.SetError(err)
+						if beh != nil {
+							_ = beh(ms)
+						} else if m.opts.Logger.V(logger.ErrorLevel) {
+							m.opts.Logger.Error(m.opts.Context, err.Error())
+						}
+					} else if sub.opts.AutoAck {
+						if err = ms.Ack(); err != nil {
+							m.opts.Logger.Errorf(m.opts.Context, "ack failed: %v", err)
+						}
+					}
+					// single processing
+				case sub.handler != nil:
+					for _, p := range ms {
+						if err = sub.handler(p); err != nil {
+							p.SetError(err)
+							if eh != nil {
+								_ = eh(p)
+							} else if m.opts.Logger.V(logger.ErrorLevel) {
+								m.opts.Logger.Error(m.opts.Context, err.Error())
+							}
+						} else if sub.opts.AutoAck {
+							if err = p.Ack(); err != nil {
+								m.opts.Logger.Errorf(m.opts.Context, "ack failed: %v", err)
+							}
+						}
+					}
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
+func (m *memoryBroker) BatchSubscribe(ctx context.Context, topic string, handler broker.BatchHandler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
+	m.RLock()
+	if !m.connected {
+		m.RUnlock()
+		return nil, broker.ErrNotConnected
+	}
+	m.RUnlock()
+
+	sid, err := id.New()
+	if err != nil {
+		return nil, err
+	}
+
+	options := broker.NewSubscribeOptions(opts...)
+
+	sub := &memorySubscriber{
+		exit:         make(chan bool, 1),
+		id:           sid,
+		topic:        topic,
+		batchhandler: handler,
+		opts:         options,
+		ctx:          ctx,
+	}
+
+	m.Lock()
+	m.subscribers[topic] = append(m.subscribers[topic], sub)
+	m.Unlock()
+
+	go func() {
+		<-sub.exit
+		m.Lock()
+		newSubscribers := make([]*memorySubscriber, 0, len(m.subscribers)-1)
+		for _, sb := range m.subscribers[topic] {
+			if sb.id == sub.id {
+				continue
+			}
+			newSubscribers = append(newSubscribers, sb)
+		}
+		m.subscribers[topic] = newSubscribers
+		m.Unlock()
+	}()
+
+	return sub, nil
+}
+
+func (m *memoryBroker) Subscribe(ctx context.Context, topic string, handler broker.Handler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
+	m.RLock()
+	if !m.connected {
+		m.RUnlock()
+		return nil, broker.ErrNotConnected
+	}
+	m.RUnlock()
+
+	sid, err := id.New()
+	if err != nil {
+		return nil, err
+	}
+
+	options := broker.NewSubscribeOptions(opts...)
+
+	sub := &memorySubscriber{
+		exit:    make(chan bool, 1),
+		id:      sid,
+		topic:   topic,
+		handler: handler,
+		opts:    options,
+		ctx:     ctx,
+	}
+
+	m.Lock()
+	m.subscribers[topic] = append(m.subscribers[topic], sub)
+	m.Unlock()
+
+	go func() {
+		<-sub.exit
+		m.Lock()
+		newSubscribers := make([]*memorySubscriber, 0, len(m.subscribers)-1)
+		for _, sb := range m.subscribers[topic] {
+			if sb.id == sub.id {
+				continue
+			}
+			newSubscribers = append(newSubscribers, sb)
+		}
+		m.subscribers[topic] = newSubscribers
+		m.Unlock()
+	}()
+
+	return sub, nil
+}
+
+func (m *memoryBroker) String() string {
+	return "memory"
+}
+
+func (m *memoryBroker) Name() string {
+	return m.opts.Name
+}
+
+func (m *memoryEvent) Topic() string {
+	return m.topic
+}
+
+func (m *memoryEvent) Message() *broker.Message {
+	switch v := m.message.(type) {
+	case *broker.Message:
+		return v
+	case []byte:
+		msg := &broker.Message{}
+		if err := m.opts.Codec.Unmarshal(v, msg); err != nil {
+			if m.opts.Logger.V(logger.ErrorLevel) {
+				m.opts.Logger.Error(m.opts.Context, "[memory]: failed to unmarshal: %v", err)
+			}
+			return nil
+		}
+		return msg
+	}
+
+	return nil
+}
+
+func (m *memoryEvent) Ack() error {
+	return nil
+}
+
+func (m *memoryEvent) Error() error {
+	return m.err
+}
+
+func (m *memoryEvent) SetError(err error) {
+	m.err = err
+}
+
+func (m *memorySubscriber) Options() broker.SubscribeOptions {
+	return m.opts
+}
+
+func (m *memorySubscriber) Topic() string {
+	return m.topic
+}
+
+func (m *memorySubscriber) Unsubscribe(ctx context.Context) error {
+	m.exit <- true
+	return nil
+}
+
+// NewBroker return new memory broker
+func NewBroker(opts ...broker.Option) broker.Broker {
+	return &memoryBroker{
+		opts:        broker.NewOptions(opts...),
+		subscribers: make(map[string][]*memorySubscriber),
+	}
+}

broker/memory/memory_test.go

@@ -5,7 +5,8 @@ import (
 	"fmt"
 	"testing"
 
-	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v3/metadata"
 )
 
 func TestMemoryBatchBroker(t *testing.T) {
@@ -19,35 +20,29 @@ func TestMemoryBatchBroker(t *testing.T) {
 	topic := "test"
 	count := 10
 
-	fn := func(evts []Message) error {
-		var err error
-		for _, evt := range evts {
-			if err = evt.Ack(); err != nil {
-				return err
-			}
-		}
-		return nil
+	fn := func(evts broker.Events) error {
+		return evts.Ack()
 	}
 
-	sub, err := b.Subscribe(ctx, topic, fn)
+	sub, err := b.BatchSubscribe(ctx, topic, fn)
 	if err != nil {
 		t.Fatalf("Unexpected error subscribing %v", err)
 	}
 
-	msgs := make([]Message, 0, count)
+	msgs := make([]*broker.Message, 0, count)
 	for i := 0; i < count; i++ {
-		message := &memoryMessage{
-			header: metadata.Metadata{
-				metadata.HeaderTopic: []string{topic},
-				"foo":                []string{"bar"},
-				"id":                 []string{fmt.Sprintf("%d", i)},
+		message := &broker.Message{
+			Header: map[string]string{
+				metadata.HeaderTopic: topic,
+				"foo":                "bar",
+				"id":                 fmt.Sprintf("%d", i),
 			},
-			body: []byte(`"hello world"`),
+			Body: []byte(`"hello world"`),
 		}
 		msgs = append(msgs, message)
 	}
 
-	if err := b.Publish(ctx, msgs); err != nil {
+	if err := b.BatchPublish(ctx, msgs); err != nil {
 		t.Fatalf("Unexpected error publishing %v", err)
 	}
 
@@ -71,8 +66,8 @@ func TestMemoryBroker(t *testing.T) {
 	topic := "test"
 	count := 10
 
-	fn := func(p Message) error {
-		return p.Ack()
+	fn := func(p broker.Event) error {
+		return nil
 	}
 
 	sub, err := b.Subscribe(ctx, topic, fn)
@@ -80,20 +75,24 @@ func TestMemoryBroker(t *testing.T) {
 		t.Fatalf("Unexpected error subscribing %v", err)
 	}
 
-	msgs := make([]Message, 0, count)
+	msgs := make([]*broker.Message, 0, count)
 	for i := 0; i < count; i++ {
-		message := &memoryMessage{
-			header: metadata.Metadata{
-				metadata.HeaderTopic: []string{topic},
-				"foo":                []string{"bar"},
-				"id":                 []string{fmt.Sprintf("%d", i)},
+		message := &broker.Message{
+			Header: map[string]string{
+				metadata.HeaderTopic: topic,
+				"foo":                "bar",
+				"id":                 fmt.Sprintf("%d", i),
 			},
-			body: []byte(`"hello world"`),
+			Body: []byte(`"hello world"`),
 		}
 		msgs = append(msgs, message)
+
+		if err := b.Publish(ctx, topic, message); err != nil {
+			t.Fatalf("Unexpected error publishing %d err: %v", i, err)
+		}
 	}
 
-	if err := b.Publish(ctx, msgs); err != nil {
+	if err := b.BatchPublish(ctx, msgs); err != nil {
 		t.Fatalf("Unexpected error publishing %v", err)
 	}
 

broker/noop.go

@@ -0,0 +1,82 @@
+package broker
+
+import (
+	"context"
+	"strings"
+)
+
+type NoopBroker struct {
+	opts Options
+}
+
+func NewBroker(opts ...Option) *NoopBroker {
+	b := &NoopBroker{opts: NewOptions(opts...)}
+	return b
+}
+
+func (b *NoopBroker) Name() string {
+	return b.opts.Name
+}
+
+func (b *NoopBroker) String() string {
+	return "noop"
+}
+
+func (b *NoopBroker) Options() Options {
+	return b.opts
+}
+
+func (b *NoopBroker) Init(opts ...Option) error {
+	for _, opt := range opts {
+		opt(&b.opts)
+	}
+	return nil
+}
+
+func (b *NoopBroker) Connect(_ context.Context) error {
+	return nil
+}
+
+func (b *NoopBroker) Disconnect(_ context.Context) error {
+	return nil
+}
+
+func (b *NoopBroker) Address() string {
+	return strings.Join(b.opts.Addrs, ",")
+}
+
+func (b *NoopBroker) BatchPublish(_ context.Context, _ []*Message, _ ...PublishOption) error {
+	return nil
+}
+
+func (b *NoopBroker) Publish(_ context.Context, _ string, _ *Message, _ ...PublishOption) error {
+	return nil
+}
+
+type NoopSubscriber struct {
+	ctx          context.Context
+	topic        string
+	handler      Handler
+	batchHandler BatchHandler
+	opts         SubscribeOptions
+}
+
+func (b *NoopBroker) BatchSubscribe(ctx context.Context, topic string, handler BatchHandler, opts ...SubscribeOption) (Subscriber, error) {
+	return &NoopSubscriber{ctx: ctx, topic: topic, opts: NewSubscribeOptions(opts...), batchHandler: handler}, nil
+}
+
+func (b *NoopBroker) Subscribe(ctx context.Context, topic string, handler Handler, opts ...SubscribeOption) (Subscriber, error) {
+	return &NoopSubscriber{ctx: ctx, topic: topic, opts: NewSubscribeOptions(opts...), handler: handler}, nil
+}
+
+func (s *NoopSubscriber) Options() SubscribeOptions {
+	return s.opts
+}
+
+func (s *NoopSubscriber) Topic() string {
+	return s.topic
+}
+
+func (s *NoopSubscriber) Unsubscribe(ctx context.Context) error {
+	return nil
+}

broker/options.go

@@ -5,14 +5,11 @@ import (
 	"crypto/tls"
 	"time"
 
-	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v4/register"
-	"go.unistack.org/micro/v4/sync"
-	"go.unistack.org/micro/v4/tracer"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // Options struct
@@ -21,8 +18,8 @@ type Options struct {
 	Tracer tracer.Tracer
 	// Register can be used for clustering
 	Register register.Register
-	// Codecs holds the codec for marshal/unmarshal
-	Codecs map[string]codec.Codec
+	// Codec holds the codec for marshal/unmarshal
+	Codec codec.Codec
 	// Logger used for logging
 	Logger logger.Logger
 	// Meter used for metrics
@@ -31,51 +28,49 @@ type Options struct {
 	Context context.Context
 	// TLSConfig holds tls.TLSConfig options
 	TLSConfig *tls.Config
-	// ErrorHandler used when broker have error while processing message
-	ErrorHandler interface{}
+	// ErrorHandler used when broker can't unmarshal incoming message
+	ErrorHandler Handler
+	// BatchErrorHandler used when broker can't unmashal incoming messages
+	BatchErrorHandler BatchHandler
 	// Name holds the broker name
 	Name string
-	// Address holds the broker address
-	Address []string
-
-	Wait *sync.WaitGroup
-
-	GracefulTimeout time.Duration
+	// Addrs holds the broker address
+	Addrs []string
 }
 
 // NewOptions create new Options
-func NewOptions(opts ...options.Option) Options {
-	newOpts := Options{
-		Register:        register.DefaultRegister,
-		Logger:          logger.DefaultLogger,
-		Context:         context.Background(),
-		Meter:           meter.DefaultMeter,
-		Codecs:          make(map[string]codec.Codec),
-		Tracer:          tracer.DefaultTracer,
-		GracefulTimeout: DefaultGracefulTimeout,
+func NewOptions(opts ...Option) Options {
+	options := Options{
+		Register: register.DefaultRegister,
+		Logger:   logger.DefaultLogger,
+		Context:  context.Background(),
+		Meter:    meter.DefaultMeter,
+		Codec:    codec.DefaultCodec,
+		Tracer:   tracer.DefaultTracer,
 	}
 	for _, o := range opts {
-		o(&newOpts)
+		o(&options)
+	}
+	return options
+}
+
+// Context sets the context option
+func Context(ctx context.Context) Option {
+	return func(o *Options) {
+		o.Context = ctx
 	}
-	return newOpts
 }
 
 // PublishOptions struct
 type PublishOptions struct {
 	// Context holds external options
 	Context context.Context
-	// Message metadata usually passed as message headers
-	Metadata metadata.Metadata
-	// Content-Type of message for marshal
-	ContentType string
-	// Topic destination
-	Topic string
 	// BodyOnly flag says the message contains raw body bytes
 	BodyOnly bool
 }
 
 // NewPublishOptions creates PublishOptions struct
-func NewPublishOptions(opts ...options.Option) PublishOptions {
+func NewPublishOptions(opts ...PublishOption) PublishOptions {
 	options := PublishOptions{
 		Context: context.Background(),
 	}
@@ -85,21 +80,16 @@ func NewPublishOptions(opts ...options.Option) PublishOptions {
 	return options
 }
 
-// PublishTopic pass topic for messages
-func PublishTopic(t string) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, t, ".Topic")
-	}
-}
-
 // SubscribeOptions struct
 type SubscribeOptions struct {
 	// Context holds external options
 	Context context.Context
-	// ErrorHandler used when broker have error while processing message
-	ErrorHandler interface{}
-	// QueueGroup holds consumer group
-	QueueGroup string
+	// ErrorHandler used when broker can't unmarshal incoming message
+	ErrorHandler Handler
+	// BatchErrorHandler used when broker can't unmashal incoming messages
+	BatchErrorHandler BatchHandler
+	// Group holds consumer group
+	Group string
 	// AutoAck flag specifies auto ack of incoming message when no error happens
 	AutoAck bool
 	// BodyOnly flag specifies that message contains only body bytes without header
@@ -110,16 +100,179 @@ type SubscribeOptions struct {
 	BatchWait time.Duration
 }
 
-// ErrorHandler will catch all broker errors that cant be handled
-// in normal way, for example Codec errors
-func ErrorHandler(h interface{}) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, h, ".ErrorHandler")
+// Option func
+type Option func(*Options)
+
+// PublishOption func
+type PublishOption func(*PublishOptions)
+
+// PublishBodyOnly publish only body of the message
+func PublishBodyOnly(b bool) PublishOption {
+	return func(o *PublishOptions) {
+		o.BodyOnly = b
 	}
 }
 
+// PublishContext sets the context
+func PublishContext(ctx context.Context) PublishOption {
+	return func(o *PublishOptions) {
+		o.Context = ctx
+	}
+}
+
+// Addrs sets the host addresses to be used by the broker
+func Addrs(addrs ...string) Option {
+	return func(o *Options) {
+		o.Addrs = addrs
+	}
+}
+
+// Codec sets the codec used for encoding/decoding used where
+// a broker does not support headers
+func Codec(c codec.Codec) Option {
+	return func(o *Options) {
+		o.Codec = c
+	}
+}
+
+// ErrorHandler will catch all broker errors that cant be handled
+// in normal way, for example Codec errors
+func ErrorHandler(h Handler) Option {
+	return func(o *Options) {
+		o.ErrorHandler = h
+	}
+}
+
+// BatchErrorHandler will catch all broker errors that cant be handled
+// in normal way, for example Codec errors
+func BatchErrorHandler(h BatchHandler) Option {
+	return func(o *Options) {
+		o.BatchErrorHandler = h
+	}
+}
+
+// SubscribeErrorHandler will catch all broker errors that cant be handled
+// in normal way, for example Codec errors
+func SubscribeErrorHandler(h Handler) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.ErrorHandler = h
+	}
+}
+
+// SubscribeBatchErrorHandler will catch all broker errors that cant be handled
+// in normal way, for example Codec errors
+func SubscribeBatchErrorHandler(h BatchHandler) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.BatchErrorHandler = h
+	}
+}
+
+// Queue sets the subscribers queue
+// Deprecated
+func Queue(name string) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.Group = name
+	}
+}
+
+// SubscribeGroup sets the name of the queue to share messages on
+func SubscribeGroup(name string) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.Group = name
+	}
+}
+
+// Register sets register option
+func Register(r register.Register) Option {
+	return func(o *Options) {
+		o.Register = r
+	}
+}
+
+// TLSConfig sets the TLS Config
+func TLSConfig(t *tls.Config) Option {
+	return func(o *Options) {
+		o.TLSConfig = t
+	}
+}
+
+// Logger sets the logger
+func Logger(l logger.Logger) Option {
+	return func(o *Options) {
+		o.Logger = l
+	}
+}
+
+// Tracer to be used for tracing
+func Tracer(t tracer.Tracer) Option {
+	return func(o *Options) {
+		o.Tracer = t
+	}
+}
+
+// Meter sets the meter
+func Meter(m meter.Meter) Option {
+	return func(o *Options) {
+		o.Meter = m
+	}
+}
+
+// Name sets the name
+func Name(n string) Option {
+	return func(o *Options) {
+		o.Name = n
+	}
+}
+
+// SubscribeContext set context
+func SubscribeContext(ctx context.Context) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.Context = ctx
+	}
+}
+
+// DisableAutoAck disables auto ack
+// Deprecated
+func DisableAutoAck() SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.AutoAck = false
+	}
+}
+
+// SubscribeAutoAck contol auto acking of messages
+// after they have been handled.
+func SubscribeAutoAck(b bool) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.AutoAck = b
+	}
+}
+
+// SubscribeBodyOnly consumes only body of the message
+func SubscribeBodyOnly(b bool) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.BodyOnly = b
+	}
+}
+
+// SubscribeBatchSize specifies max batch size
+func SubscribeBatchSize(n int) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.BatchSize = n
+	}
+}
+
+// SubscribeBatchWait specifies max batch wait time
+func SubscribeBatchWait(td time.Duration) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.BatchWait = td
+	}
+}
+
+// SubscribeOption func
+type SubscribeOption func(*SubscribeOptions)
+
 // NewSubscribeOptions creates new SubscribeOptions
-func NewSubscribeOptions(opts ...options.Option) SubscribeOptions {
+func NewSubscribeOptions(opts ...SubscribeOption) SubscribeOptions {
 	options := SubscribeOptions{
 		AutoAck: true,
 		Context: context.Background(),
@@ -129,39 +282,3 @@ func NewSubscribeOptions(opts ...options.Option) SubscribeOptions {
 	}
 	return options
 }
-
-// SubscribeAutoAck contol auto acking of messages
-// after they have been handled.
-func SubscribeAutoAck(b bool) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, b, ".AutoAck")
-	}
-}
-
-// BodyOnly transfer only body without
-func BodyOnly(b bool) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, b, ".BodyOnly")
-	}
-}
-
-// SubscribeBatchSize specifies max batch size
-func SubscribeBatchSize(n int) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, n, ".BatchSize")
-	}
-}
-
-// SubscribeBatchWait specifies max batch wait time
-func SubscribeBatchWait(td time.Duration) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, td, ".BatchWait")
-	}
-}
-
-// SubscribeQueueGroup sets the shared queue name distributed messages across subscribers
-func SubscribeQueueGroup(n string) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, n, ".QueueGroup")
-	}
-}

broker/subscriber.go

@@ -1,98 +0,0 @@
-package broker
-
-import (
-	"fmt"
-	"reflect"
-	"strings"
-	"unicode"
-	"unicode/utf8"
-)
-
-const (
-	subSig      = "func(context.Context, interface{}) error"
-	batchSubSig = "func([]context.Context, []interface{}) error"
-)
-
-// Precompute the reflect type for error. Can't use error directly
-// because Typeof takes an empty interface value. This is annoying.
-var typeOfError = reflect.TypeOf((*error)(nil)).Elem()
-
-// Is this an exported - upper case - name?
-func isExported(name string) bool {
-	r, _ := utf8.DecodeRuneInString(name)
-	return unicode.IsUpper(r)
-}
-
-// Is this type exported or a builtin?
-func isExportedOrBuiltinType(t reflect.Type) bool {
-	for t.Kind() == reflect.Ptr {
-		t = t.Elem()
-	}
-	// PkgPath will be non-empty even for an exported type,
-	// so we need to check the type name as well.
-	return isExported(t.Name()) || t.PkgPath() == ""
-}
-
-// ValidateSubscriber func signature
-func ValidateSubscriber(sub interface{}) error {
-	typ := reflect.TypeOf(sub)
-	var argType reflect.Type
-	switch typ.Kind() {
-	case reflect.Func:
-		name := "Func"
-		switch typ.NumIn() {
-		case 1: // func(Message) error
-
-		case 2: // func(context.Context, Message) error or func(context.Context, []Message) error
-			argType = typ.In(2)
-			// if sub.Options().Batch {
-			if argType.Kind() != reflect.Slice {
-				return fmt.Errorf("subscriber %v dont have required signature %s", name, batchSubSig)
-			}
-			if strings.Compare(fmt.Sprintf("%v", argType), "[]interface{}") == 0 {
-				return fmt.Errorf("subscriber %v dont have required signaure %s", name, batchSubSig)
-			}
-		//	}
-		default:
-			return fmt.Errorf("subscriber %v takes wrong number of args: %v required signature %s or %s", name, typ.NumIn(), subSig, batchSubSig)
-		}
-		if !isExportedOrBuiltinType(argType) {
-			return fmt.Errorf("subscriber %v argument type not exported: %v", name, argType)
-		}
-		if typ.NumOut() != 1 {
-			return fmt.Errorf("subscriber %v has wrong number of return values: %v require signature %s or %s",
-				name, typ.NumOut(), subSig, batchSubSig)
-		}
-		if returnType := typ.Out(0); returnType != typeOfError {
-			return fmt.Errorf("subscriber %v returns %v not error", name, returnType.String())
-		}
-	default:
-		hdlr := reflect.ValueOf(sub)
-		name := reflect.Indirect(hdlr).Type().Name()
-
-		for m := 0; m < typ.NumMethod(); m++ {
-			method := typ.Method(m)
-			switch method.Type.NumIn() {
-			case 3:
-				argType = method.Type.In(2)
-			default:
-				return fmt.Errorf("subscriber %v.%v takes wrong number of args: %v required signature %s or %s",
-					name, method.Name, method.Type.NumIn(), subSig, batchSubSig)
-			}
-
-			if !isExportedOrBuiltinType(argType) {
-				return fmt.Errorf("%v argument type not exported: %v", name, argType)
-			}
-			if method.Type.NumOut() != 1 {
-				return fmt.Errorf(
-					"subscriber %v.%v has wrong number of return values: %v require signature %s or %s",
-					name, method.Name, method.Type.NumOut(), subSig, batchSubSig)
-			}
-			if returnType := method.Type.Out(0); returnType != typeOfError {
-				return fmt.Errorf("subscriber %v.%v returns %v not error", name, method.Name, returnType.String())
-			}
-		}
-	}
-
-	return nil
-}

client/backoff.go

@@ -5,7 +5,7 @@ import (
 	"math"
 	"time"
 
-	"go.unistack.org/micro/v4/util/backoff"
+	"go.unistack.org/micro/v3/util/backoff"
 )
 
 // BackoffFunc is the backoff call func

client/client.go

@@ -1,12 +1,12 @@
 // Package client is an interface for an RPC client
-package client // import "go.unistack.org/micro/v4/client"
+package client // import "go.unistack.org/micro/v3/client"
 
 import (
 	"context"
 	"time"
 
-	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v4/options"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/metadata"
 )
 
 var (
@@ -22,8 +22,6 @@ var (
 	DefaultRetries = 0
 	// DefaultRequestTimeout is the default request timeout
 	DefaultRequestTimeout = time.Second * 5
-	// DefaultDialTimeout the default dial timeout
-	DefaultDialTimeout = time.Second * 5
 	// DefaultPoolSize sets the connection pool size
 	DefaultPoolSize = 100
 	// DefaultPoolTTL sets the connection pool ttl
@@ -35,14 +33,25 @@ var (
 // It also supports bidirectional streaming of requests.
 type Client interface {
 	Name() string
-	Init(opts ...options.Option) error
+	Init(opts ...Option) error
 	Options() Options
-	NewRequest(service string, endpoint string, req interface{}, opts ...options.Option) Request
-	Call(ctx context.Context, req Request, rsp interface{}, opts ...options.Option) error
-	Stream(ctx context.Context, req Request, opts ...options.Option) (Stream, error)
+	NewMessage(topic string, msg interface{}, opts ...MessageOption) Message
+	NewRequest(service string, endpoint string, req interface{}, opts ...RequestOption) Request
+	Call(ctx context.Context, req Request, rsp interface{}, opts ...CallOption) error
+	Stream(ctx context.Context, req Request, opts ...CallOption) (Stream, error)
+	Publish(ctx context.Context, msg Message, opts ...PublishOption) error
+	BatchPublish(ctx context.Context, msg []Message, opts ...PublishOption) error
 	String() string
 }
 
+// Message is the interface for publishing asynchronously
+type Message interface {
+	Topic() string
+	Payload() interface{}
+	ContentType() string
+	Metadata() metadata.Metadata
+}
+
 // Request is the interface for a synchronous request used by Call or Stream
 type Request interface {
 	// The service to call
@@ -59,22 +68,16 @@ type Request interface {
 	Codec() codec.Codec
 	// indicates whether the request will be a streaming one rather than unary
 	Stream() bool
-	// Header data
-	// Header() metadata.Metadata
 }
 
 // Response is the response received from a service
 type Response interface {
 	// Read the response
 	Codec() codec.Codec
-	// The content type
-	// ContentType() string
 	// Header data
-	// Header() metadata.Metadata
+	Header() metadata.Metadata
 	// Read the undecoded response
 	Read() ([]byte, error)
-	// The unencoded request body
-	// Body() interface{}
 }
 
 // Stream is the interface for a bidirectional synchronous stream
@@ -100,3 +103,18 @@ type Stream interface {
 	// CloseSend closes the send direction of the stream
 	CloseSend() error
 }
+
+// Option used by the Client
+type Option func(*Options)
+
+// CallOption used by Call or Stream
+type CallOption func(*CallOptions)
+
+// PublishOption used by Publish
+type PublishOption func(*PublishOptions)
+
+// MessageOption used by NewMessage
+type MessageOption func(*MessageOptions)
+
+// RequestOption used by NewRequest
+type RequestOption func(*RequestOptions)

client/client_call_options.go

@@ -2,24 +2,22 @@ package client
 
 import (
 	"context"
-
-	"go.unistack.org/micro/v4/options"
 )
 
 type clientCallOptions struct {
 	Client
-	opts []options.Option
+	opts []CallOption
 }
 
-func (s *clientCallOptions) Call(ctx context.Context, req Request, rsp interface{}, opts ...options.Option) error {
+func (s *clientCallOptions) Call(ctx context.Context, req Request, rsp interface{}, opts ...CallOption) error {
 	return s.Client.Call(ctx, req, rsp, append(s.opts, opts...)...)
 }
 
-func (s *clientCallOptions) Stream(ctx context.Context, req Request, opts ...options.Option) (Stream, error) {
+func (s *clientCallOptions) Stream(ctx context.Context, req Request, opts ...CallOption) (Stream, error) {
 	return s.Client.Stream(ctx, req, append(s.opts, opts...)...)
 }
 
 // NewClientCallOptions add CallOption to every call
-func NewClientCallOptions(c Client, opts ...options.Option) Client {
+func NewClientCallOptions(c Client, opts ...CallOption) Client {
 	return &clientCallOptions{c, opts}
 }

client/client_call_options_test.go

@@ -4,8 +4,6 @@ import (
 	"context"
 	"testing"
 	"time"
-
-	"go.unistack.org/micro/v4/options"
 )
 
 func TestNewClientCallOptions(t *testing.T) {
@@ -15,11 +13,11 @@ func TestNewClientCallOptions(t *testing.T) {
 		return fn
 	}
 	c := NewClientCallOptions(NewClient(),
-		options.Address("127.0.0.1"),
+		WithAddress("127.0.0.1"),
 		WithCallWrapper(w),
-		RequestTimeout(1*time.Millisecond),
-		Retries(0),
-		Backoff(BackoffInterval(10*time.Millisecond, 100*time.Millisecond)),
+		WithRequestTimeout(1*time.Millisecond),
+		WithRetries(0),
+		WithBackoff(BackoffInterval(10*time.Millisecond, 100*time.Millisecond)),
 	)
 	_ = c.Call(context.TODO(), c.NewRequest("service", "endpoint", nil), nil)
 	if !flag {

client/context.go

@@ -22,3 +22,33 @@ func NewContext(ctx context.Context, c Client) context.Context {
 	}
 	return context.WithValue(ctx, clientKey{}, c)
 }
+
+// SetPublishOption returns a function to setup a context with given value
+func SetPublishOption(k, v interface{}) PublishOption {
+	return func(o *PublishOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}
+
+// SetCallOption returns a function to setup a context with given value
+func SetCallOption(k, v interface{}) CallOption {
+	return func(o *CallOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}
+
+// SetOption returns a function to setup a context with given value
+func SetOption(k, v interface{}) Option {
+	return func(o *Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}

client/context_test.go

@@ -38,3 +38,36 @@ func TestNewNilContext(t *testing.T) {
 		t.Fatal("NewContext not works")
 	}
 }
+
+func TestSetPublishOption(t *testing.T) {
+	type key struct{}
+	o := SetPublishOption(key{}, "test")
+	opts := &PublishOptions{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetPublishOption not works")
+	}
+}
+
+func TestSetCallOption(t *testing.T) {
+	type key struct{}
+	o := SetCallOption(key{}, "test")
+	opts := &CallOptions{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetCallOption not works")
+	}
+}
+
+func TestSetOption(t *testing.T) {
+	type key struct{}
+	o := SetOption(key{}, "test")
+	opts := &Options{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetOption not works")
+	}
+}

client/lookup.go

@@ -4,8 +4,8 @@ import (
 	"context"
 	"sort"
 
-	"go.unistack.org/micro/v4/errors"
-	"go.unistack.org/micro/v4/router"
+	"go.unistack.org/micro/v3/errors"
+	"go.unistack.org/micro/v3/router"
 )
 
 // LookupFunc is used to lookup routes for a service

client/noop.go

@@ -3,14 +3,14 @@ package client
 import (
 	"context"
 	"fmt"
+	"os"
 	"time"
 
-	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v4/errors"
-	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v4/selector"
-	"go.unistack.org/micro/v4/semconv"
+	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/errors"
+	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/selector"
 )
 
 // DefaultCodecs will be used to encode/decode data
@@ -22,6 +22,12 @@ type noopClient struct {
 	opts Options
 }
 
+type noopMessage struct {
+	topic   string
+	payload interface{}
+	opts    MessageOptions
+}
+
 type noopRequest struct {
 	body        interface{}
 	codec       codec.Codec
@@ -33,12 +39,16 @@ type noopRequest struct {
 }
 
 // NewClient returns new noop client
-func NewClient(opts ...options.Option) Client {
+func NewClient(opts ...Option) Client {
 	nc := &noopClient{opts: NewOptions(opts...)}
 	// wrap in reverse
 
 	c := Client(nc)
 
+	for i := len(nc.opts.Wrappers); i > 0; i-- {
+		c = nc.opts.Wrappers[i-1](c)
+	}
+
 	return c
 }
 
@@ -133,6 +143,22 @@ func (n *noopStream) CloseSend() error {
 	return nil
 }
 
+func (n *noopMessage) Topic() string {
+	return n.topic
+}
+
+func (n *noopMessage) Payload() interface{} {
+	return n.payload
+}
+
+func (n *noopMessage) ContentType() string {
+	return n.opts.ContentType
+}
+
+func (n *noopMessage) Metadata() metadata.Metadata {
+	return n.opts.Metadata
+}
+
 func (n *noopClient) newCodec(contentType string) (codec.Codec, error) {
 	if cf, ok := n.opts.Codecs[contentType]; ok {
 		return cf, nil
@@ -143,7 +169,7 @@ func (n *noopClient) newCodec(contentType string) (codec.Codec, error) {
 	return nil, codec.ErrUnknownContentType
 }
 
-func (n *noopClient) Init(opts ...options.Option) error {
+func (n *noopClient) Init(opts ...Option) error {
 	for _, o := range opts {
 		o(&n.opts)
 	}
@@ -158,7 +184,7 @@ func (n *noopClient) String() string {
 	return "noop"
 }
 
-func (n *noopClient) Call(ctx context.Context, req Request, rsp interface{}, opts ...options.Option) error {
+func (n *noopClient) Call(ctx context.Context, req Request, rsp interface{}, opts ...CallOption) error {
 	// make a copy of call opts
 	callOpts := n.opts.CallOptions
 	for _, opt := range opts {
@@ -175,7 +201,7 @@ func (n *noopClient) Call(ctx context.Context, req Request, rsp interface{}, opt
 	} else {
 		// got a deadline so no need to setup context
 		// but we need to set the timeout we pass along
-		opt := RequestTimeout(time.Until(d))
+		opt := WithRequestTimeout(time.Until(d))
 		opt(&callOpts)
 	}
 
@@ -260,9 +286,6 @@ func (n *noopClient) Call(ctx context.Context, req Request, rsp interface{}, opt
 	ch := make(chan error, callOpts.Retries)
 	var gerr error
 
-	ts := time.Now()
-	endpoint := fmt.Sprintf("%s.%s", req.Service(), req.Endpoint())
-	n.opts.Meter.Counter(semconv.ClientRequestInflight, "endpoint", endpoint).Inc()
 	for i := 0; i <= callOpts.Retries; i++ {
 		go func() {
 			ch <- call(i)
@@ -290,16 +313,6 @@ func (n *noopClient) Call(ctx context.Context, req Request, rsp interface{}, opt
 		}
 	}
 
-	if gerr != nil {
-		n.opts.Meter.Counter(semconv.ClientRequestTotal, "endpoint", endpoint, "status", "failure").Inc()
-	} else {
-		n.opts.Meter.Counter(semconv.ClientRequestTotal, "endpoint", endpoint, "status", "success").Inc()
-	}
-	n.opts.Meter.Counter(semconv.ClientRequestInflight, "endpoint", endpoint).Dec()
-	te := time.Since(ts)
-	n.opts.Meter.Summary(semconv.ClientRequestLatencyMicroseconds, "endpoint", endpoint).Update(te.Seconds())
-	n.opts.Meter.Histogram(semconv.ClientRequestDurationSeconds, "endpoint", endpoint).Update(te.Seconds())
-
 	return gerr
 }
 
@@ -307,11 +320,16 @@ func (n *noopClient) call(ctx context.Context, addr string, req Request, rsp int
 	return nil
 }
 
-func (n *noopClient) NewRequest(service, endpoint string, req interface{}, opts ...options.Option) Request {
+func (n *noopClient) NewRequest(service, endpoint string, req interface{}, opts ...RequestOption) Request {
 	return &noopRequest{service: service, endpoint: endpoint}
 }
 
-func (n *noopClient) Stream(ctx context.Context, req Request, opts ...options.Option) (Stream, error) {
+func (n *noopClient) NewMessage(topic string, msg interface{}, opts ...MessageOption) Message {
+	options := NewMessageOptions(append([]MessageOption{MessageContentType(n.opts.ContentType)}, opts...)...)
+	return &noopMessage{topic: topic, payload: msg, opts: options}
+}
+
+func (n *noopClient) Stream(ctx context.Context, req Request, opts ...CallOption) (Stream, error) {
 	var err error
 
 	// make a copy of call opts
@@ -330,7 +348,7 @@ func (n *noopClient) Stream(ctx context.Context, req Request, opts ...options.Op
 	} else {
 		// got a deadline so no need to setup context
 		// but we need to set the timeout we pass along
-		o := StreamTimeout(time.Until(d))
+		o := WithStreamTimeout(time.Until(d))
 		o(&callOpts)
 	}
 
@@ -397,15 +415,7 @@ func (n *noopClient) Stream(ctx context.Context, req Request, opts ...options.Op
 
 		node := next()
 
-		// ts := time.Now()
-		endpoint := fmt.Sprintf("%s.%s", req.Service(), req.Endpoint())
-		n.opts.Meter.Counter(semconv.ClientRequestInflight, "endpoint", endpoint).Inc()
 		stream, cerr := n.stream(ctx, node, req, callOpts)
-		if cerr != nil {
-			n.opts.Meter.Counter(semconv.ClientRequestTotal, "endpoint", endpoint, "status", "failure").Inc()
-		} else {
-			n.opts.Meter.Counter(semconv.ClientRequestTotal, "endpoint", endpoint, "status", "success").Inc()
-		}
 
 		// record the result of the call to inform future routing decisions
 		if verr := n.opts.Selector.Record(node, cerr); verr != nil {
@@ -459,6 +469,77 @@ func (n *noopClient) Stream(ctx context.Context, req Request, opts ...options.Op
 	return nil, grr
 }
 
-func (n *noopClient) stream(ctx context.Context, addr string, req Request, opts CallOptions) (*noopStream, error) {
+func (n *noopClient) stream(ctx context.Context, addr string, req Request, opts CallOptions) (Stream, error) {
 	return &noopStream{}, nil
 }
+
+func (n *noopClient) BatchPublish(ctx context.Context, ps []Message, opts ...PublishOption) error {
+	return n.publish(ctx, ps, opts...)
+}
+
+func (n *noopClient) Publish(ctx context.Context, p Message, opts ...PublishOption) error {
+	return n.publish(ctx, []Message{p}, opts...)
+}
+
+func (n *noopClient) publish(ctx context.Context, ps []Message, opts ...PublishOption) error {
+	options := NewPublishOptions(opts...)
+
+	msgs := make([]*broker.Message, 0, len(ps))
+
+	// get proxy
+	exchange := ""
+	if v, ok := os.LookupEnv("MICRO_PROXY"); ok {
+		exchange = v
+	}
+	// get the exchange
+	if len(options.Exchange) > 0 {
+		exchange = options.Exchange
+	}
+
+	omd, ok := metadata.FromOutgoingContext(ctx)
+	if !ok {
+		omd = metadata.New(0)
+	}
+
+	for _, p := range ps {
+		md := metadata.Copy(omd)
+		md[metadata.HeaderContentType] = p.ContentType()
+		topic := p.Topic()
+		if len(exchange) > 0 {
+			topic = exchange
+		}
+		md[metadata.HeaderTopic] = topic
+		iter := p.Metadata().Iterator()
+		var k, v string
+		for iter.Next(&k, &v) {
+			md.Set(k, v)
+		}
+
+		var body []byte
+
+		// passed in raw data
+		if d, ok := p.Payload().(*codec.Frame); ok {
+			body = d.Data
+		} else {
+			// use codec for payload
+			cf, err := n.newCodec(p.ContentType())
+			if err != nil {
+				return errors.InternalServerError("go.micro.client", err.Error())
+			}
+
+			// set the body
+			b, err := cf.Marshal(p.Payload())
+			if err != nil {
+				return errors.InternalServerError("go.micro.client", err.Error())
+			}
+			body = b
+		}
+
+		msgs = append(msgs, &broker.Message{Header: md, Body: body})
+	}
+
+	return n.opts.Broker.BatchPublish(ctx, msgs,
+		broker.PublishContext(options.Context),
+		broker.PublishBodyOnly(options.BodyOnly),
+	)
+}

client/options.go

@@ -6,25 +6,31 @@ import (
 	"net"
 	"time"
 
-	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v4/router"
-	"go.unistack.org/micro/v4/selector"
-	"go.unistack.org/micro/v4/selector/random"
-	"go.unistack.org/micro/v4/tracer"
+	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/network/transport"
+	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v3/router"
+	"go.unistack.org/micro/v3/selector"
+	"go.unistack.org/micro/v3/selector/random"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // Options holds client options
 type Options struct {
+	// Transport used for transfer messages
+	Transport transport.Transport
 	// Selector used to select needed address
 	Selector selector.Selector
 	// Logger used to log messages
 	Logger logger.Logger
 	// Tracer used for tracing
 	Tracer tracer.Tracer
+	// Broker used to publish messages
+	Broker broker.Broker
 	// Meter used for metrics
 	Meter meter.Meter
 	// Context is used for external options
@@ -43,6 +49,8 @@ type Options struct {
 	ContentType string
 	// Name is the client name
 	Name string
+	// Wrappers contains wrappers
+	Wrappers []Wrapper
 	// CallOptions contains default CallOptions
 	CallOptions CallOptions
 	// PoolSize connection pool size
@@ -51,12 +59,10 @@ type Options struct {
 	PoolTTL time.Duration
 	// ContextDialer used to connect
 	ContextDialer func(context.Context, string) (net.Conn, error)
-	// Hooks may contains Client func wrapper
-	Hooks options.Hooks
 }
 
 // NewCallOptions creates new call options struct
-func NewCallOptions(opts ...options.Option) CallOptions {
+func NewCallOptions(opts ...CallOption) CallOptions {
 	options := CallOptions{}
 	for _, o := range opts {
 		o(&options)
@@ -105,14 +111,58 @@ type CallOptions struct {
 }
 
 // ContextDialer pass ContextDialer to client
-func ContextDialer(fn func(context.Context, string) (net.Conn, error)) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, fn, ".ContextDialer")
+func ContextDialer(fn func(context.Context, string) (net.Conn, error)) Option {
+	return func(o *Options) {
+		o.ContextDialer = fn
 	}
 }
 
+// Context pass context to client
+func Context(ctx context.Context) Option {
+	return func(o *Options) {
+		o.Context = ctx
+	}
+}
+
+// NewPublishOptions create new PublishOptions struct from option
+func NewPublishOptions(opts ...PublishOption) PublishOptions {
+	options := PublishOptions{}
+	for _, o := range opts {
+		o(&options)
+	}
+	return options
+}
+
+// PublishOptions holds publish options
+type PublishOptions struct {
+	// Context used for external options
+	Context context.Context
+	// Exchange topic exchange name
+	Exchange string
+	// BodyOnly will publish only message body
+	BodyOnly bool
+}
+
+// NewMessageOptions creates message options struct
+func NewMessageOptions(opts ...MessageOption) MessageOptions {
+	options := MessageOptions{Metadata: metadata.New(1)}
+	for _, o := range opts {
+		o(&options)
+	}
+	return options
+}
+
+// MessageOptions holds client message options
+type MessageOptions struct {
+	// Metadata additional metadata
+	Metadata metadata.Metadata
+	// ContentType specify content-type of message
+	// deprecated
+	ContentType string
+}
+
 // NewRequestOptions creates new RequestOptions struct
-func NewRequestOptions(opts ...options.Option) RequestOptions {
+func NewRequestOptions(opts ...RequestOption) RequestOptions {
 	options := RequestOptions{}
 	for _, o := range opts {
 		o(&options)
@@ -131,7 +181,7 @@ type RequestOptions struct {
 }
 
 // NewOptions creates new options struct
-func NewOptions(opts ...options.Option) Options {
+func NewOptions(opts ...Option) Options {
 	options := Options{
 		Context:     context.Background(),
 		ContentType: DefaultContentType,
@@ -142,16 +192,18 @@ func NewOptions(opts ...options.Option) Options {
 			Retry:          DefaultRetry,
 			Retries:        DefaultRetries,
 			RequestTimeout: DefaultRequestTimeout,
-			DialTimeout:    DefaultDialTimeout,
+			DialTimeout:    transport.DefaultDialTimeout,
 		},
-		Lookup:   LookupRoute,
-		PoolSize: DefaultPoolSize,
-		PoolTTL:  DefaultPoolTTL,
-		Selector: random.NewSelector(),
-		Logger:   logger.DefaultLogger,
-		Meter:    meter.DefaultMeter,
-		Tracer:   tracer.DefaultTracer,
-		Router:   router.DefaultRouter,
+		Lookup:    LookupRoute,
+		PoolSize:  DefaultPoolSize,
+		PoolTTL:   DefaultPoolTTL,
+		Selector:  random.NewSelector(),
+		Logger:    logger.DefaultLogger,
+		Broker:    broker.DefaultBroker,
+		Meter:     meter.DefaultMeter,
+		Tracer:    tracer.DefaultTracer,
+		Router:    router.DefaultRouter,
+		Transport: transport.DefaultTransport,
 	}
 
 	for _, o := range opts {
@@ -161,131 +213,381 @@ func NewOptions(opts ...options.Option) Options {
 	return options
 }
 
+// Broker to be used for pub/sub
+func Broker(b broker.Broker) Option {
+	return func(o *Options) {
+		o.Broker = b
+	}
+}
+
+// Tracer to be used for tracing
+func Tracer(t tracer.Tracer) Option {
+	return func(o *Options) {
+		o.Tracer = t
+	}
+}
+
+// Logger to be used for log mesages
+func Logger(l logger.Logger) Option {
+	return func(o *Options) {
+		o.Logger = l
+	}
+}
+
+// Meter to be used for metrics
+func Meter(m meter.Meter) Option {
+	return func(o *Options) {
+		o.Meter = m
+	}
+}
+
+// Codec to be used to encode/decode requests for a given content type
+func Codec(contentType string, c codec.Codec) Option {
+	return func(o *Options) {
+		o.Codecs[contentType] = c
+	}
+}
+
+// ContentType used by default if not specified
+func ContentType(ct string) Option {
+	return func(o *Options) {
+		o.ContentType = ct
+	}
+}
+
 // Proxy sets the proxy address
-func Proxy(addr string) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, addr, ".Proxy")
+func Proxy(addr string) Option {
+	return func(o *Options) {
+		o.Proxy = addr
 	}
 }
 
 // PoolSize sets the connection pool size
-func PoolSize(d int) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, d, ".PoolSize")
+func PoolSize(d int) Option {
+	return func(o *Options) {
+		o.PoolSize = d
 	}
 }
 
 // PoolTTL sets the connection pool ttl
-func PoolTTL(td time.Duration) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, td, ".PoolTTL")
+func PoolTTL(d time.Duration) Option {
+	return func(o *Options) {
+		o.PoolTTL = d
+	}
+}
+
+// Transport to use for communication e.g http, rabbitmq, etc
+func Transport(t transport.Transport) Option {
+	return func(o *Options) {
+		o.Transport = t
+	}
+}
+
+// Register sets the routers register
+func Register(r register.Register) Option {
+	return func(o *Options) {
+		if o.Router != nil {
+			_ = o.Router.Init(router.Register(r))
+		}
+	}
+}
+
+// Router is used to lookup routes for a service
+func Router(r router.Router) Option {
+	return func(o *Options) {
+		o.Router = r
 	}
 }
 
 // Selector is used to select a route
-func Selector(s selector.Selector) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, s, ".Selector")
+func Selector(s selector.Selector) Option {
+	return func(o *Options) {
+		o.Selector = s
+	}
+}
+
+// Wrap adds a wrapper to the list of options passed into the client
+func Wrap(w Wrapper) Option {
+	return func(o *Options) {
+		o.Wrappers = append(o.Wrappers, w)
+	}
+}
+
+// WrapCall adds a wrapper to the list of CallFunc wrappers
+func WrapCall(cw ...CallWrapper) Option {
+	return func(o *Options) {
+		o.CallOptions.CallWrappers = append(o.CallOptions.CallWrappers, cw...)
 	}
 }
 
 // Backoff is used to set the backoff function used when retrying Calls
-func Backoff(fn BackoffFunc) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, fn, ".Backoff")
+func Backoff(fn BackoffFunc) Option {
+	return func(o *Options) {
+		o.CallOptions.Backoff = fn
+	}
+}
+
+// Name sets the client name
+func Name(n string) Option {
+	return func(o *Options) {
+		o.Name = n
 	}
 }
 
 // Lookup sets the lookup function to use for resolving service names
-func Lookup(fn LookupFunc) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, fn, ".Lookup")
+func Lookup(l LookupFunc) Option {
+	return func(o *Options) {
+		o.Lookup = l
 	}
 }
 
-// WithCallWrapper sets the retry function to be used when re-trying.
-func WithCallWrapper(fn CallWrapper) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, fn, ".CallWrappers")
+// TLSConfig specifies a *tls.Config
+func TLSConfig(t *tls.Config) Option {
+	return func(o *Options) {
+		// set the internal tls
+		o.TLSConfig = t
+
+		// set the default transport if one is not
+		// already set. Required for Init call below.
+
+		// set the transport tls
+		_ = o.Transport.Init(
+			transport.TLSConfig(t),
+		)
 	}
 }
 
 // Retries sets the retry count when making the request.
-func Retries(n int) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, n, ".Retries")
+func Retries(i int) Option {
+	return func(o *Options) {
+		o.CallOptions.Retries = i
 	}
 }
 
 // Retry sets the retry function to be used when re-trying.
-func Retry(fn RetryFunc) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, fn, ".Retry")
+func Retry(fn RetryFunc) Option {
+	return func(o *Options) {
+		o.CallOptions.Retry = fn
 	}
 }
 
 // RequestTimeout is the request timeout.
-func RequestTimeout(td time.Duration) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, td, ".RequestTimeout")
+func RequestTimeout(d time.Duration) Option {
+	return func(o *Options) {
+		o.CallOptions.RequestTimeout = d
 	}
 }
 
 // StreamTimeout sets the stream timeout
-func StreamTimeout(td time.Duration) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, td, ".StreamTimeout")
+func StreamTimeout(d time.Duration) Option {
+	return func(o *Options) {
+		o.CallOptions.StreamTimeout = d
 	}
 }
 
 // DialTimeout sets the dial timeout
-func DialTimeout(td time.Duration) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, td, ".DialTimeout")
+func DialTimeout(d time.Duration) Option {
+	return func(o *Options) {
+		o.CallOptions.DialTimeout = d
+	}
+}
+
+// WithExchange sets the exchange to route a message through
+// Deprecated
+func WithExchange(e string) PublishOption {
+	return func(o *PublishOptions) {
+		o.Exchange = e
+	}
+}
+
+// PublishExchange sets the exchange to route a message through
+func PublishExchange(e string) PublishOption {
+	return func(o *PublishOptions) {
+		o.Exchange = e
+	}
+}
+
+// WithBodyOnly publish only message body
+// DERECATED
+func WithBodyOnly(b bool) PublishOption {
+	return func(o *PublishOptions) {
+		o.BodyOnly = b
+	}
+}
+
+// PublishBodyOnly publish only message body
+func PublishBodyOnly(b bool) PublishOption {
+	return func(o *PublishOptions) {
+		o.BodyOnly = b
+	}
+}
+
+// PublishContext sets the context in publish options
+func PublishContext(ctx context.Context) PublishOption {
+	return func(o *PublishOptions) {
+		o.Context = ctx
+	}
+}
+
+// WithContextDialer pass ContextDialer to client call
+func WithContextDialer(fn func(context.Context, string) (net.Conn, error)) CallOption {
+	return func(o *CallOptions) {
+		o.ContextDialer = fn
+	}
+}
+
+// WithContentType specifies call content type
+func WithContentType(ct string) CallOption {
+	return func(o *CallOptions) {
+		o.ContentType = ct
+	}
+}
+
+// WithAddress sets the remote addresses to use rather than using service discovery
+func WithAddress(a ...string) CallOption {
+	return func(o *CallOptions) {
+		o.Address = a
+	}
+}
+
+// WithCallWrapper is a CallOption which adds to the existing CallFunc wrappers
+func WithCallWrapper(cw ...CallWrapper) CallOption {
+	return func(o *CallOptions) {
+		o.CallWrappers = append(o.CallWrappers, cw...)
+	}
+}
+
+// WithBackoff is a CallOption which overrides that which
+// set in Options.CallOptions
+func WithBackoff(fn BackoffFunc) CallOption {
+	return func(o *CallOptions) {
+		o.Backoff = fn
+	}
+}
+
+// WithRetry is a CallOption which overrides that which
+// set in Options.CallOptions
+func WithRetry(fn RetryFunc) CallOption {
+	return func(o *CallOptions) {
+		o.Retry = fn
+	}
+}
+
+// WithRetries is a CallOption which overrides that which
+// set in Options.CallOptions
+func WithRetries(i int) CallOption {
+	return func(o *CallOptions) {
+		o.Retries = i
 	}
 }
 
 // WithResponseMetadata is a CallOption which adds metadata.Metadata to Options.CallOptions
-func ResponseMetadata(md *metadata.Metadata) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, md, ".ResponseMetadata")
+func WithResponseMetadata(md *metadata.Metadata) CallOption {
+	return func(o *CallOptions) {
+		o.ResponseMetadata = md
 	}
 }
 
 // WithRequestMetadata is a CallOption which adds metadata.Metadata to Options.CallOptions
-func RequestMetadata(md metadata.Metadata) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, metadata.Copy(md), ".RequestMetadata")
+func WithRequestMetadata(md metadata.Metadata) CallOption {
+	return func(o *CallOptions) {
+		o.RequestMetadata = md
 	}
 }
 
-// AuthToken is a CallOption which overrides the
+// WithRequestTimeout is a CallOption which overrides that which
+// set in Options.CallOptions
+func WithRequestTimeout(d time.Duration) CallOption {
+	return func(o *CallOptions) {
+		o.RequestTimeout = d
+	}
+}
+
+// WithStreamTimeout sets the stream timeout
+func WithStreamTimeout(d time.Duration) CallOption {
+	return func(o *CallOptions) {
+		o.StreamTimeout = d
+	}
+}
+
+// WithDialTimeout is a CallOption which overrides that which
+// set in Options.CallOptions
+func WithDialTimeout(d time.Duration) CallOption {
+	return func(o *CallOptions) {
+		o.DialTimeout = d
+	}
+}
+
+// WithAuthToken is a CallOption which overrides the
 // authorization header with the services own auth token
-func AuthToken(t string) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, t, ".AuthToken")
+func WithAuthToken(t string) CallOption {
+	return func(o *CallOptions) {
+		o.AuthToken = t
 	}
 }
 
-// Network is a CallOption which sets the network attribute
-func Network(n string) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, n, ".Network")
+// WithNetwork is a CallOption which sets the network attribute
+func WithNetwork(n string) CallOption {
+	return func(o *CallOptions) {
+		o.Network = n
+	}
+}
+
+// WithRouter sets the router to use for this call
+func WithRouter(r router.Router) CallOption {
+	return func(o *CallOptions) {
+		o.Router = r
+	}
+}
+
+// WithSelector sets the selector to use for this call
+func WithSelector(s selector.Selector) CallOption {
+	return func(o *CallOptions) {
+		o.Selector = s
 	}
 }
 
-/*
 // WithSelectOptions sets the options to pass to the selector for this call
-func WithSelectOptions(sops ...selector.SelectOption) options.Option {
+func WithSelectOptions(sops ...selector.SelectOption) CallOption {
 	return func(o *CallOptions) {
 		o.SelectOptions = sops
 	}
 }
-*/
 
-// StreamingRequest specifies that request is streaming
-func StreamingRequest(b bool) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, b, ".Stream")
+// WithMessageContentType sets the message content type
+// Deprecated
+func WithMessageContentType(ct string) MessageOption {
+	return func(o *MessageOptions) {
+		o.Metadata.Set(metadata.HeaderContentType, ct)
+		o.ContentType = ct
+	}
+}
+
+// MessageContentType sets the message content type
+func MessageContentType(ct string) MessageOption {
+	return func(o *MessageOptions) {
+		o.Metadata.Set(metadata.HeaderContentType, ct)
+		o.ContentType = ct
+	}
+}
+
+// MessageMetadata sets the message metadata
+func MessageMetadata(k, v string) MessageOption {
+	return func(o *MessageOptions) {
+		o.Metadata.Set(k, v)
+	}
+}
+
+// StreamingRequest specifies that request is streaming
+func StreamingRequest(b bool) RequestOption {
+	return func(o *RequestOptions) {
+		o.Stream = b
+	}
+}
+
+// RequestContentType specifies request content type
+func RequestContentType(ct string) RequestOption {
+	return func(o *RequestOptions) {
+		o.ContentType = ct
 	}
 }

client/retry.go

@@ -3,7 +3,7 @@ package client
 import (
 	"context"
 
-	"go.unistack.org/micro/v4/errors"
+	"go.unistack.org/micro/v3/errors"
 )
 
 // RetryFunc that returning either false or a non-nil error will result in the call not being retried

client/retry_test.go

@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"testing"
 
-	"go.unistack.org/micro/v4/errors"
+	"go.unistack.org/micro/v3/errors"
 )
 
 func TestRetryAlways(t *testing.T) {

client/test_request.go

@@ -1,7 +1,7 @@
 package client
 
 import (
-	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v3/codec"
 )
 
 type testRequest struct {

codec/codec.go

@@ -1,11 +1,11 @@
 // Package codec is an interface for encoding messages
-package codec // import "go.unistack.org/micro/v4/codec"
+package codec // import "go.unistack.org/micro/v3/codec"
 
 import (
 	"errors"
 	"io"
 
-	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v3/metadata"
 )
 
 // Message types

codec/frame.proto

@@ -1,4 +1,4 @@
-// Copyright 2021-2023 Unistack LLC
+// Copyright 2021 Unistack LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -17,7 +17,7 @@ syntax = "proto3";
 package micro.codec;
 
 option cc_enable_arenas = true;
-option go_package = "go.unistack.org/micro/v4/codec;codec";
+option go_package = "go.unistack.org/micro/v3/codec;codec";
 option java_multiple_files = true;
 option java_outer_classname = "MicroCodec";
 option java_package = "micro.codec";

codec/options.go

@@ -3,9 +3,9 @@ package codec
 import (
 	"context"
 
-	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v4/tracer"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // Option func

config/config.go

@@ -1,13 +1,11 @@
 // Package config is an interface for dynamic configuration.
-package config // import "go.unistack.org/micro/v4/config"
+package config // import "go.unistack.org/micro/v3/config"
 
 import (
 	"context"
 	"errors"
 	"reflect"
 	"time"
-
-	"go.unistack.org/micro/v4/options"
 )
 
 type Validator interface {
@@ -39,15 +37,15 @@ type Config interface {
 	// Name returns name of config
 	Name() string
 	// Init the config
-	Init(opts ...options.Option) error
+	Init(opts ...Option) error
 	// Options in the config
 	Options() Options
 	// Load config from sources
-	Load(context.Context, ...options.Option) error
+	Load(context.Context, ...LoadOption) error
 	// Save config to sources
-	Save(context.Context, ...options.Option) error
+	Save(context.Context, ...SaveOption) error
 	// Watch a config for changes
-	Watch(context.Context, ...options.Option) (Watcher, error)
+	Watch(context.Context, ...WatchOption) (Watcher, error)
 	// String returns config type name
 	String() string
 }
@@ -61,7 +59,7 @@ type Watcher interface {
 }
 
 // Load loads config from config sources
-func Load(ctx context.Context, cs []Config, opts ...options.Option) error {
+func Load(ctx context.Context, cs []Config, opts ...LoadOption) error {
 	var err error
 	for _, c := range cs {
 		if err = c.Init(); err != nil {
@@ -133,7 +131,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Error(ctx, c.String()+" BeforeLoad error "+err.Error())
+				c.Options().Logger.Errorf(ctx, "%s BeforeLoad err: %v", c.String(), err)
 				if !c.Options().AllowFail {
 					return err
 				}
@@ -148,7 +146,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Error(ctx, c.String()+" AfterLoad error "+err.Error())
+				c.Options().Logger.Errorf(ctx, "%s AfterLoad err: %v", c.String(), err)
 				if !c.Options().AllowFail {
 					return err
 				}
@@ -163,7 +161,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Error(ctx, c.String()+" BeforeSave error "+err.Error())
+				c.Options().Logger.Errorf(ctx, "%s BeforeSave err: %v", c.String(), err)
 				if !c.Options().AllowFail {
 					return err
 				}
@@ -178,7 +176,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Error(ctx, c.String()+" AfterSave error "+err.Error())
+				c.Options().Logger.Errorf(ctx, "%s AfterSave err: %v", c.String(), err)
 				if !c.Options().AllowFail {
 					return err
 				}
@@ -193,7 +191,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Error(ctx, c.String()+" BeforeInit error "+err.Error())
+				c.Options().Logger.Errorf(ctx, "%s BeforeInit err: %v", c.String(), err)
 				if !c.Options().AllowFail {
 					return err
 				}
@@ -208,7 +206,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Error(ctx, c.String()+" AfterInit error "+err.Error())
+				c.Options().Logger.Errorf(ctx, "%s AfterInit err: %v", c.String(), err)
 				if !c.Options().AllowFail {
 					return err
 				}

config/context.go

@@ -22,3 +22,43 @@ func NewContext(ctx context.Context, c Config) context.Context {
 	}
 	return context.WithValue(ctx, configKey{}, c)
 }
+
+// SetOption returns a function to setup a context with given value
+func SetOption(k, v interface{}) Option {
+	return func(o *Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}
+
+// SetSaveOption returns a function to setup a context with given value
+func SetSaveOption(k, v interface{}) SaveOption {
+	return func(o *SaveOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}
+
+// SetLoadOption returns a function to setup a context with given value
+func SetLoadOption(k, v interface{}) LoadOption {
+	return func(o *LoadOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}
+
+// SetWatchOption returns a function to setup a context with given value
+func SetWatchOption(k, v interface{}) WatchOption {
+	return func(o *WatchOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}

config/context_test.go

@@ -40,3 +40,47 @@ func TestNewContext(t *testing.T) {
 		t.Fatal("NewContext not works")
 	}
 }
+
+func TestSetOption(t *testing.T) {
+	type key struct{}
+	o := SetOption(key{}, "test")
+	opts := &Options{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetOption not works")
+	}
+}
+
+func TestSetSaveOption(t *testing.T) {
+	type key struct{}
+	o := SetSaveOption(key{}, "test")
+	opts := &SaveOptions{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetSaveOption not works")
+	}
+}
+
+func TestSetLoadOption(t *testing.T) {
+	type key struct{}
+	o := SetLoadOption(key{}, "test")
+	opts := &LoadOptions{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetLoadOption not works")
+	}
+}
+
+func TestSetWatchOption(t *testing.T) {
+	type key struct{}
+	o := SetWatchOption(key{}, "test")
+	opts := &WatchOptions{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetWatchOption not works")
+	}
+}

config/default.go

@@ -9,10 +9,9 @@ import (
 
 	"dario.cat/mergo"
 	"github.com/google/uuid"
-	"go.unistack.org/micro/v4/options"
-	mid "go.unistack.org/micro/v4/util/id"
-	rutil "go.unistack.org/micro/v4/util/reflect"
-	mtime "go.unistack.org/micro/v4/util/time"
+	mid "go.unistack.org/micro/v3/util/id"
+	rutil "go.unistack.org/micro/v3/util/reflect"
+	mtime "go.unistack.org/micro/v3/util/time"
 )
 
 type defaultConfig struct {
@@ -23,7 +22,7 @@ func (c *defaultConfig) Options() Options {
 	return c.opts
 }
 
-func (c *defaultConfig) Init(opts ...options.Option) error {
+func (c *defaultConfig) Init(opts ...Option) error {
 	for _, o := range opts {
 		o(&c.opts)
 	}
@@ -39,7 +38,7 @@ func (c *defaultConfig) Init(opts ...options.Option) error {
 	return nil
 }
 
-func (c *defaultConfig) Load(ctx context.Context, opts ...options.Option) error {
+func (c *defaultConfig) Load(ctx context.Context, opts ...LoadOption) error {
 	if c.opts.SkipLoad != nil && c.opts.SkipLoad(ctx, c) {
 		return nil
 	}
@@ -190,7 +189,7 @@ func fillValue(value reflect.Value, val string) error {
 				return err
 			}
 			value.Set(reflect.ValueOf(v))
-		case value.Type().String() == "time.Duration" && value.Type().PkgPath() == "go.unistack.org/micro/v4/util/time":
+		case value.Type().String() == "time.Duration" && value.Type().PkgPath() == "go.unistack.org/micro/v3/util/time":
 			v, err := mtime.ParseDuration(val)
 			if err != nil {
 				return err
@@ -296,7 +295,7 @@ func fillValues(valueOf reflect.Value, tname string) error {
 	return nil
 }
 
-func (c *defaultConfig) Save(ctx context.Context, _ ...options.Option) error {
+func (c *defaultConfig) Save(ctx context.Context, _ ...SaveOption) error {
 	if c.opts.SkipSave != nil && c.opts.SkipSave(ctx, c) {
 		return nil
 	}
@@ -320,12 +319,12 @@ func (c *defaultConfig) Name() string {
 	return c.opts.Name
 }
 
-func (c *defaultConfig) Watch(ctx context.Context, opts ...options.Option) (Watcher, error) {
+func (c *defaultConfig) Watch(ctx context.Context, opts ...WatchOption) (Watcher, error) {
 	return nil, ErrWatcherNotImplemented
 }
 
 // NewConfig returns new default config source
-func NewConfig(opts ...options.Option) Config {
+func NewConfig(opts ...Option) Config {
 	options := NewOptions(opts...)
 	if len(options.StructTag) == 0 {
 		options.StructTag = "default"

config/default_test.go

@@ -6,9 +6,9 @@ import (
 	"testing"
 	"time"
 
-	"go.unistack.org/micro/v4/config"
-	mid "go.unistack.org/micro/v4/util/id"
-	mtime "go.unistack.org/micro/v4/util/time"
+	"go.unistack.org/micro/v3/config"
+	mid "go.unistack.org/micro/v3/util/id"
+	mtime "go.unistack.org/micro/v3/util/time"
 )
 
 type cfg struct {
@@ -31,9 +31,6 @@ func (c *cfg) Validate() error {
 	if c.IntValue != 10 {
 		return fmt.Errorf("invalid IntValue %d != %d", 10, c.IntValue)
 	}
-	if c.MapValue["key1"] != true {
-		return fmt.Errorf("invalid MapValue %t != %t", true, c.MapValue["key1"])
-	}
 	return nil
 }
 
@@ -108,19 +105,3 @@ func TestValidate(t *testing.T) {
 		t.Fatal(err)
 	}
 }
-
-func TestString(t *testing.T) {
-	cfg := config.NewConfig()
-	res := cfg.String()
-	if res != "default" {
-		t.Fatalf("string value invalid: %s", res)
-	}
-}
-
-func TestName(t *testing.T) {
-	cfg := config.NewConfig()
-	res := cfg.Name()
-	if res != "" {
-		t.Fatal("name value not empty")
-	}
-}

config/options.go

@@ -4,11 +4,10 @@ import (
 	"context"
 	"time"
 
-	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v4/tracer"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // Options hold the config options
@@ -49,8 +48,11 @@ type Options struct {
 	SkipSave func(context.Context, Config) bool
 }
 
+// Option function signature
+type Option func(o *Options)
+
 // NewOptions new options struct with filed values
-func NewOptions(opts ...options.Option) Options {
+func NewOptions(opts ...Option) Options {
 	options := Options{
 		Logger:  logger.DefaultLogger,
 		Meter:   meter.DefaultMeter,
@@ -64,6 +66,9 @@ func NewOptions(opts ...options.Option) Options {
 	return options
 }
 
+// LoadOption function signature
+type LoadOption func(o *LoadOptions)
+
 // LoadOptions struct
 type LoadOptions struct {
 	Struct   interface{}
@@ -73,7 +78,7 @@ type LoadOptions struct {
 }
 
 // NewLoadOptions create LoadOptions struct with provided opts
-func NewLoadOptions(opts ...options.Option) LoadOptions {
+func NewLoadOptions(opts ...LoadOption) LoadOptions {
 	options := LoadOptions{}
 	for _, o := range opts {
 		o(&options)
@@ -82,27 +87,44 @@ func NewLoadOptions(opts ...options.Option) LoadOptions {
 }
 
 // LoadOverride override values when load
-func LoadOverride(b bool) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, b, ".Override")
+func LoadOverride(b bool) LoadOption {
+	return func(o *LoadOptions) {
+		o.Override = b
 	}
 }
 
 // LoadAppend override values when load
-func LoadAppend(b bool) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, b, ".Append")
+func LoadAppend(b bool) LoadOption {
+	return func(o *LoadOptions) {
+		o.Append = b
 	}
 }
 
+// LoadStruct override struct for loading
+func LoadStruct(src interface{}) LoadOption {
+	return func(o *LoadOptions) {
+		o.Struct = src
+	}
+}
+
+// SaveOption function signature
+type SaveOption func(o *SaveOptions)
+
 // SaveOptions struct
 type SaveOptions struct {
 	Struct  interface{}
 	Context context.Context
 }
 
+// SaveStruct override struct for save to config
+func SaveStruct(src interface{}) SaveOption {
+	return func(o *SaveOptions) {
+		o.Struct = src
+	}
+}
+
 // NewSaveOptions fill SaveOptions struct
-func NewSaveOptions(opts ...options.Option) SaveOptions {
+func NewSaveOptions(opts ...SaveOption) SaveOptions {
 	options := SaveOptions{}
 	for _, o := range opts {
 		o(&options)
@@ -111,65 +133,100 @@ func NewSaveOptions(opts ...options.Option) SaveOptions {
 }
 
 // AllowFail allows config source to fail
-func AllowFail(b bool) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, b, ".AllowFail")
+func AllowFail(b bool) Option {
+	return func(o *Options) {
+		o.AllowFail = b
 	}
 }
 
 // BeforeInit run funcs before config Init
-func BeforeInit(fn ...func(context.Context, Config) error) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, fn, ".BeforeInit")
+func BeforeInit(fn ...func(context.Context, Config) error) Option {
+	return func(o *Options) {
+		o.BeforeInit = fn
 	}
 }
 
 // AfterInit run funcs after config Init
-func AfterInit(fn ...func(context.Context, Config) error) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, fn, ".AfterInit")
+func AfterInit(fn ...func(context.Context, Config) error) Option {
+	return func(o *Options) {
+		o.AfterInit = fn
 	}
 }
 
 // BeforeLoad run funcs before config load
-func BeforeLoad(fn ...func(context.Context, Config) error) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, fn, ".BeforeLoad")
+func BeforeLoad(fn ...func(context.Context, Config) error) Option {
+	return func(o *Options) {
+		o.BeforeLoad = fn
 	}
 }
 
 // AfterLoad run funcs after config load
-func AfterLoad(fn ...func(context.Context, Config) error) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, fn, ".AfterLoad")
+func AfterLoad(fn ...func(context.Context, Config) error) Option {
+	return func(o *Options) {
+		o.AfterLoad = fn
 	}
 }
 
 // BeforeSave run funcs before save
-func BeforeSave(fn ...func(context.Context, Config) error) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, fn, ".BeforeSave")
+func BeforeSave(fn ...func(context.Context, Config) error) Option {
+	return func(o *Options) {
+		o.BeforeSave = fn
 	}
 }
 
 // AfterSave run fncs after save
-func AfterSave(fn ...func(context.Context, Config) error) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, fn, ".AfterSave")
+func AfterSave(fn ...func(context.Context, Config) error) Option {
+	return func(o *Options) {
+		o.AfterSave = fn
+	}
+}
+
+// Context pass context
+func Context(ctx context.Context) Option {
+	return func(o *Options) {
+		o.Context = ctx
+	}
+}
+
+// Codec sets the source codec
+func Codec(c codec.Codec) Option {
+	return func(o *Options) {
+		o.Codec = c
+	}
+}
+
+// Logger sets the logger
+func Logger(l logger.Logger) Option {
+	return func(o *Options) {
+		o.Logger = l
+	}
+}
+
+// Tracer to be used for tracing
+func Tracer(t tracer.Tracer) Option {
+	return func(o *Options) {
+		o.Tracer = t
 	}
 }
 
 // Struct used as config
-func Struct(v interface{}) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, v, ".Struct")
+func Struct(v interface{}) Option {
+	return func(o *Options) {
+		o.Struct = v
 	}
 }
 
 // StructTag sets the struct tag that used for filling
-func StructTag(name string) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, name, ".StructTag")
+func StructTag(name string) Option {
+	return func(o *Options) {
+		o.StructTag = name
+	}
+}
+
+// Name sets the name
+func Name(n string) Option {
+	return func(o *Options) {
+		o.Name = n
 	}
 }
 
@@ -187,8 +244,11 @@ type WatchOptions struct {
 	Coalesce bool
 }
 
+// WatchOption func signature
+type WatchOption func(*WatchOptions)
+
 // NewWatchOptions create WatchOptions struct with provided opts
-func NewWatchOptions(opts ...options.Option) WatchOptions {
+func NewWatchOptions(opts ...WatchOption) WatchOptions {
 	options := WatchOptions{
 		Context:     context.Background(),
 		MinInterval: DefaultWatcherMinInterval,
@@ -200,20 +260,31 @@ func NewWatchOptions(opts ...options.Option) WatchOptions {
 	return options
 }
 
-// Coalesce controls watch event combining
-func WatchCoalesce(b bool) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, b, ".Coalesce")
+// WatchContext pass context
+func WatchContext(ctx context.Context) WatchOption {
+	return func(o *WatchOptions) {
+		o.Context = ctx
+	}
+}
+
+// WatchCoalesce controls watch event combining
+func WatchCoalesce(b bool) WatchOption {
+	return func(o *WatchOptions) {
+		o.Coalesce = b
 	}
 }
 
 // WatchInterval specifies min and max time.Duration for pulling changes
-func WatchInterval(min, max time.Duration) options.Option {
-	return func(src interface{}) error {
-		var err error
-		if err = options.Set(src, min, ".MinInterval"); err == nil {
-			err = options.Set(src, max, ".MaxInterval")
-		}
-		return err
+func WatchInterval(min, max time.Duration) WatchOption {
+	return func(o *WatchOptions) {
+		o.MinInterval = min
+		o.MaxInterval = max
+	}
+}
+
+// WatchStruct overrides struct for fill
+func WatchStruct(src interface{}) WatchOption {
+	return func(o *WatchOptions) {
+		o.Struct = src
 	}
 }

database/dsn.go

@@ -75,80 +75,78 @@ func ParseDSN(dsn string) (*Config, error) {
 	// Find last '/' that goes before dbname
 	foundSlash := false
 	for i := len(dsn) - 1; i >= 0; i-- {
-		if dsn[i] != '/' {
-			continue
-		}
+		if dsn[i] == '/' {
+			foundSlash = true
+			var j, k int
 
-		foundSlash = true
-		var j, k int
-
-		// left part is empty if i <= 0
-		if i > 0 {
-			// Find the first ':' in dsn
-			for j = i; j >= 0; j-- {
-				if dsn[j] == ':' {
-					cfg.Scheme = dsn[0:j]
+			// left part is empty if i <= 0
+			if i > 0 {
+				// Find the first ':' in dsn
+				for j = i; j >= 0; j-- {
+					if dsn[j] == ':' {
+						cfg.Scheme = dsn[0:j]
+					}
 				}
-			}
 
-			// [username[:password]@][host]
-			// Find the last '@' in dsn[:i]
-			for j = i; j >= 0; j-- {
-				if dsn[j] == '@' {
-					// username[:password]
-					// Find the second ':' in dsn[:j]
-					for k = 0; k < j; k++ {
-						if dsn[k] == ':' {
-							if cfg.Scheme == dsn[:k] {
-								continue
+				// [username[:password]@][host]
+				// Find the last '@' in dsn[:i]
+				for j = i; j >= 0; j-- {
+					if dsn[j] == '@' {
+						// username[:password]
+						// Find the second ':' in dsn[:j]
+						for k = 0; k < j; k++ {
+							if dsn[k] == ':' {
+								if cfg.Scheme == dsn[:k] {
+									continue
+								}
+								var err error
+								cfg.Password, err = url.PathUnescape(dsn[k+1 : j])
+								if err != nil {
+									return nil, err
+								}
+								break
 							}
-							var err error
-							cfg.Password, err = url.PathUnescape(dsn[k+1 : j])
-							if err != nil {
-								return nil, err
-							}
-							break
 						}
+						cfg.Username = dsn[len(cfg.Scheme)+3 : k]
+						break
 					}
-					cfg.Username = dsn[len(cfg.Scheme)+3 : k]
+				}
+
+				for k = j + 1; k < i; k++ {
+					if dsn[k] == ':' {
+						cfg.Host = dsn[j+1 : k]
+						cfg.Port = dsn[k+1 : i]
+						break
+					}
+				}
+
+			}
+
+			// dbname[?param1=value1&...&paramN=valueN]
+			// Find the first '?' in dsn[i+1:]
+			for j = i + 1; j < len(dsn); j++ {
+				if dsn[j] == '?' {
+					parts := strings.Split(dsn[j+1:], "&")
+					cfg.Params = make([]string, 0, len(parts)*2)
+					for _, p := range parts {
+						k, v, found := strings.Cut(p, "=")
+						if !found {
+							continue
+						}
+						cfg.Params = append(cfg.Params, k, v)
+					}
+
 					break
 				}
 			}
-
-			for k = j + 1; k < i; k++ {
-				if dsn[k] == ':' {
-					cfg.Host = dsn[j+1 : k]
-					cfg.Port = dsn[k+1 : i]
-					break
-				}
+			var err error
+			dbname := dsn[i+1 : j]
+			if cfg.Database, err = url.PathUnescape(dbname); err != nil {
+				return nil, fmt.Errorf("invalid dbname %q: %w", dbname, err)
 			}
 
+			break
 		}
-
-		// dbname[?param1=value1&...&paramN=valueN]
-		// Find the first '?' in dsn[i+1:]
-		for j = i + 1; j < len(dsn); j++ {
-			if dsn[j] == '?' {
-				parts := strings.Split(dsn[j+1:], "&")
-				cfg.Params = make([]string, 0, len(parts)*2)
-				for _, p := range parts {
-					k, v, found := strings.Cut(p, "=")
-					if !found {
-						continue
-					}
-					cfg.Params = append(cfg.Params, k, v)
-				}
-
-				break
-			}
-		}
-		var err error
-		dbname := dsn[i+1 : j]
-		if cfg.Database, err = url.PathUnescape(dbname); err != nil {
-			return nil, fmt.Errorf("invalid dbname %q: %w", dbname, err)
-		}
-
-		break
 	}
 
 	if !foundSlash && len(dsn) > 0 {

errors/errors.go

@@ -1,14 +1,20 @@
 // Package errors provides a way to return detailed information
 // for an RPC request error. The error is normally JSON encoded.
-package errors // import "go.unistack.org/micro/v4/errors"
+package errors // import "go.unistack.org/micro/v3/errors"
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
+	"io"
 	"net/http"
 	"strconv"
 	"strings"
+
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
 )
 
 var (
@@ -340,3 +346,135 @@ func addslashes(str string) string {
 	}
 	return buf.String()
 }
+
+type retryableError struct {
+	err error
+}
+
+// Retryable returns error that can be retried later
+func Retryable(err error) error {
+	return &retryableError{err: err}
+}
+
+type IsRetryableFunc func(error) bool
+
+var (
+	RetrayableOracleErrors = []IsRetryableFunc{
+		func(err error) bool {
+			errmsg := err.Error()
+			switch {
+			case strings.Contains(errmsg, `ORA-`):
+				return true
+			case strings.Contains(errmsg, `can not assign`):
+				return true
+			case strings.Contains(errmsg, `can't assign`):
+				return true
+			}
+			return false
+		},
+	}
+	RetrayablePostgresErrors = []IsRetryableFunc{
+		func(err error) bool {
+			errmsg := err.Error()
+			switch {
+			case strings.Contains(errmsg, `number of field descriptions must equal number of`):
+				return true
+			case strings.Contains(errmsg, `not a pointer`):
+				return true
+			case strings.Contains(errmsg, `values, but dst struct has only`):
+				return true
+			case strings.Contains(errmsg, `struct doesn't have corresponding row field`):
+				return true
+			case strings.Contains(errmsg, `cannot find field`):
+				return true
+			case strings.Contains(errmsg, `cannot scan`) || strings.Contains(errmsg, `cannot convert`):
+				return true
+			case strings.Contains(errmsg, `failed to connect to`):
+				return true
+			}
+			return false
+		},
+	}
+	RetryableMicroErrors = []IsRetryableFunc{
+		func(err error) bool {
+			switch verr := err.(type) {
+			case *Error:
+				switch verr.Code {
+				case 401, 403, 408, 500, 501, 502, 503, 504:
+					return true
+				default:
+					return false
+				}
+			case *retryableError:
+				return true
+			}
+			return false
+		},
+	}
+	RetryableGoErrors = []IsRetryableFunc{
+		func(err error) bool {
+			switch verr := err.(type) {
+			case interface{ SafeToRetry() bool }:
+				return verr.SafeToRetry()
+			case interface{ Timeout() bool }:
+				return verr.Timeout()
+			}
+			switch {
+			case errors.Is(err, io.EOF), errors.Is(err, io.ErrUnexpectedEOF):
+				return true
+			case errors.Is(err, context.DeadlineExceeded):
+				return true
+			case errors.Is(err, io.ErrClosedPipe), errors.Is(err, io.ErrShortBuffer), errors.Is(err, io.ErrShortWrite):
+				return true
+			}
+			return false
+		},
+	}
+	RetryableGrpcErrors = []IsRetryableFunc{
+		func(err error) bool {
+			st, ok := status.FromError(err)
+			if !ok {
+				return false
+			}
+			switch st.Code() {
+			case codes.Unavailable, codes.ResourceExhausted:
+				return true
+			case codes.DeadlineExceeded:
+				return true
+			case codes.Internal:
+				switch {
+				case strings.Contains(st.Message(), `transport: received the unexpected content-type "text/html; charset=UTF-8"`):
+					return true
+				case strings.Contains(st.Message(), io.ErrUnexpectedEOF.Error()):
+					return true
+				case strings.Contains(st.Message(), `stream terminated by RST_STREAM with error code: INTERNAL_ERROR`):
+					return true
+				}
+			}
+			return false
+		},
+	}
+)
+
+// Unwrap provides error wrapping
+func (e *retryableError) Unwrap() error {
+	return e.err
+}
+
+// Error returns the error string
+func (e *retryableError) Error() string {
+	if e.err == nil {
+		return ""
+	}
+	return e.err.Error()
+}
+
+// IsRetryable checks error for ability to retry later
+func IsRetryable(err error, fns ...IsRetryableFunc) bool {
+	for _, fn := range fns {
+		if ok := fn(err); ok {
+			return true
+		}
+	}
+	return false
+}

errors/errors.proto

@@ -1,4 +1,4 @@
-// Copyright 2021-2023 Unistack LLC
+// Copyright 2021 Unistack LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -17,7 +17,7 @@ syntax = "proto3";
 package micro.errors;
 
 option cc_enable_arenas = true;
-option go_package = "go.unistack.org/micro/v4/errors;errors";
+option go_package = "go.unistack.org/micro/v3/errors;errors";
 option java_multiple_files = true;
 option java_outer_classname = "MicroErrors";
 option java_package = "micro.errors";

errors/errors_test.go

@@ -8,6 +8,13 @@ import (
 	"testing"
 )
 
+func TestIsRetrayable(t *testing.T) {
+	err := fmt.Errorf("ORA-")
+	if !IsRetryable(err, RetrayableOracleErrors...) {
+		t.Fatalf("IsRetrayable not works")
+	}
+}
+
 func TestMarshalJSON(t *testing.T) {
 	e := InternalServerError("id", "err: %v", fmt.Errorf("err: %v", `xxx: "UNIX_TIMESTAMP": invalid identifier`))
 	_, err := json.Marshal(e)

event.go

@@ -0,0 +1,27 @@
+package micro
+
+import (
+	"context"
+
+	"go.unistack.org/micro/v3/client"
+)
+
+// Event is used to publish messages to a topic
+type Event interface {
+	// Publish publishes a message to the event topic
+	Publish(ctx context.Context, msg interface{}, opts ...client.PublishOption) error
+}
+
+type event struct {
+	c     client.Client
+	topic string
+}
+
+// NewEvent creates a new event publisher
+func NewEvent(topic string, c client.Client) Event {
+	return &event{c, topic}
+}
+
+func (e *event) Publish(ctx context.Context, msg interface{}, opts ...client.PublishOption) error {
+	return e.c.Publish(ctx, e.c.NewMessage(e.topic, msg), opts...)
+}

flow/context.go

@@ -22,3 +22,13 @@ func NewContext(ctx context.Context, f Flow) context.Context {
 	}
 	return context.WithValue(ctx, flowKey{}, f)
 }
+
+// SetOption returns a function to setup a context with given value
+func SetOption(k, v interface{}) Option {
+	return func(o *Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}

flow/context_test.go

@@ -40,3 +40,14 @@ func TestNewContext(t *testing.T) {
 		t.Fatal("NewContext not works")
 	}
 }
+
+func TestSetOption(t *testing.T) {
+	type key struct{}
+	o := SetOption(key{}, "test")
+	opts := &Options{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetOption not works")
+	}
+}

flow/default.go

@@ -6,14 +6,12 @@ import (
 	"sync"
 
 	"github.com/silas/dag"
-	"go.unistack.org/micro/v4/client"
-	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v4/options"
-	moptions "go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v4/store"
-	"go.unistack.org/micro/v4/util/id"
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/store"
+	"go.unistack.org/micro/v3/util/id"
 )
 
 type microFlow struct {
@@ -165,7 +163,7 @@ func (w *microWorkflow) Resume(ctx context.Context, id string) error {
 	return workflowStore.Write(ctx, "status", &codec.Frame{Data: []byte(StatusRunning.String())})
 }
 
-func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...options.Option) (string, error) {
+func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...ExecuteOption) (string, error) {
 	w.Lock()
 	if !w.init {
 		if err := w.g.Validate(); err != nil {
@@ -190,7 +188,7 @@ func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...optio
 	steps, err := w.getSteps(options.Start, options.Reverse)
 	if err != nil {
 		if werr := workflowStore.Write(w.opts.Context, "status", &codec.Frame{Data: []byte(StatusPending.String())}); werr != nil {
-			w.opts.Logger.Error(w.opts.Context, "store write error", "error", werr.Error())
+			w.opts.Logger.Errorf(w.opts.Context, "store error: %v", werr)
 		}
 		return "", err
 	}
@@ -202,19 +200,19 @@ func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...optio
 	nctx, cancel := context.WithCancel(ctx)
 	defer cancel()
 
-	nopts := make([]moptions.Option, 0, len(opts)+5)
+	nopts := make([]ExecuteOption, 0, len(opts)+5)
 
 	nopts = append(nopts,
-		moptions.Client(w.opts.Client),
-		moptions.Tracer(w.opts.Tracer),
-		moptions.Logger(w.opts.Logger),
-		moptions.Meter(w.opts.Meter),
+		ExecuteClient(w.opts.Client),
+		ExecuteTracer(w.opts.Tracer),
+		ExecuteLogger(w.opts.Logger),
+		ExecuteMeter(w.opts.Meter),
 	)
 	nopts = append(nopts, opts...)
 	done := make(chan struct{})
 
 	if werr := workflowStore.Write(w.opts.Context, "status", &codec.Frame{Data: []byte(StatusRunning.String())}); werr != nil {
-		w.opts.Logger.Error(w.opts.Context, "store write error", "error", werr.Error())
+		w.opts.Logger.Errorf(w.opts.Context, "store error: %v", werr)
 		return eid, werr
 	}
 	for idx := range steps {
@@ -239,7 +237,7 @@ func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...optio
 					return
 				}
 				if w.opts.Logger.V(logger.TraceLevel) {
-					w.opts.Logger.Trace(nctx, fmt.Sprintf("step will be executed %v", steps[idx][nidx]))
+					w.opts.Logger.Tracef(nctx, "will be executed %v", steps[idx][nidx])
 				}
 				cstep := steps[idx][nidx]
 				// nolint: nestif
@@ -259,21 +257,21 @@ func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...optio
 						if serr != nil {
 							step.SetStatus(StatusFailure)
 							if werr := stepStore.Write(ctx, step.ID()+w.opts.Store.Options().Separator+"rsp", serr); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
-								w.opts.Logger.Error(ctx, "store write error", "error", werr.Error())
+								w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
 							}
 							if werr := stepStore.Write(ctx, step.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusFailure.String())}); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
-								w.opts.Logger.Error(ctx, "store write error", "error", werr.Error())
+								w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
 							}
 							cherr <- serr
 							return
 						}
 						if werr := stepStore.Write(ctx, step.ID()+w.opts.Store.Options().Separator+"rsp", rsp); werr != nil {
-							w.opts.Logger.Error(ctx, "store write error", "error", werr.Error())
+							w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
 							cherr <- werr
 							return
 						}
 						if werr := stepStore.Write(ctx, step.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusSuccess.String())}); werr != nil {
-							w.opts.Logger.Error(ctx, "store write error", "error", werr.Error())
+							w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
 							cherr <- werr
 							return
 						}
@@ -292,16 +290,16 @@ func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...optio
 					if serr != nil {
 						cstep.SetStatus(StatusFailure)
 						if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"rsp", serr); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
-							w.opts.Logger.Error(ctx, "store write error", "error", werr.Error())
+							w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
 						}
 						if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusFailure.String())}); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
-							w.opts.Logger.Error(ctx, "store write error", "error", werr.Error())
+							w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
 						}
 						cherr <- serr
 						return
 					}
 					if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"rsp", rsp); werr != nil {
-						w.opts.Logger.Error(ctx, "store write error", "error", werr.Error())
+						w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
 						cherr <- werr
 						return
 					}
@@ -319,7 +317,7 @@ func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...optio
 		return eid, nil
 	}
 
-	w.opts.Logger.Trace(ctx, "wait for finish or error")
+	logger.Tracef(ctx, "wait for finish or error")
 	select {
 	case <-nctx.Done():
 		err = nctx.Err()
@@ -335,15 +333,15 @@ func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...optio
 	switch {
 	case nctx.Err() != nil:
 		if werr := workflowStore.Write(w.opts.Context, "status", &codec.Frame{Data: []byte(StatusAborted.String())}); werr != nil {
-			w.opts.Logger.Error(w.opts.Context, "store write error", "error", werr.Error())
+			w.opts.Logger.Errorf(w.opts.Context, "store error: %v", werr)
 		}
 	case err == nil:
 		if werr := workflowStore.Write(w.opts.Context, "status", &codec.Frame{Data: []byte(StatusSuccess.String())}); werr != nil {
-			w.opts.Logger.Error(w.opts.Context, "store write error", "error", werr.Error())
+			w.opts.Logger.Errorf(w.opts.Context, "store error: %v", werr)
 		}
 	case err != nil:
 		if werr := workflowStore.Write(w.opts.Context, "status", &codec.Frame{Data: []byte(StatusFailure.String())}); werr != nil {
-			w.opts.Logger.Error(w.opts.Context, "store write error", "error", werr.Error())
+			w.opts.Logger.Errorf(w.opts.Context, "store error: %v", werr)
 		}
 	}
 
@@ -351,7 +349,7 @@ func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...optio
 }
 
 // NewFlow create new flow
-func NewFlow(opts ...options.Option) Flow {
+func NewFlow(opts ...Option) Flow {
 	options := NewOptions(opts...)
 	return &microFlow{opts: options}
 }
@@ -360,7 +358,7 @@ func (f *microFlow) Options() Options {
 	return f.opts
 }
 
-func (f *microFlow) Init(opts ...options.Option) error {
+func (f *microFlow) Init(opts ...Option) error {
 	for _, o := range opts {
 		o(&f.opts)
 	}
@@ -489,17 +487,17 @@ func (s *microCallStep) SetStatus(status Status) {
 	s.status = status
 }
 
-func (s *microCallStep) Execute(ctx context.Context, req *Message, opts ...options.Option) (*Message, error) {
+func (s *microCallStep) Execute(ctx context.Context, req *Message, opts ...ExecuteOption) (*Message, error) {
 	options := NewExecuteOptions(opts...)
 	if options.Client == nil {
 		return nil, ErrMissingClient
 	}
 	rsp := &codec.Frame{}
-	copts := []moptions.Option{client.Retries(0)}
+	copts := []client.CallOption{client.WithRetries(0)}
 	if options.Timeout > 0 {
 		copts = append(copts,
-			client.RequestTimeout(options.Timeout),
-			client.DialTimeout(options.Timeout))
+			client.WithRequestTimeout(options.Timeout),
+			client.WithDialTimeout(options.Timeout))
 	}
 	nctx := metadata.NewOutgoingContext(ctx, req.Header)
 	err := options.Client.Call(nctx, options.Client.NewRequest(s.service, s.method, &codec.Frame{Data: req.Body}), rsp, copts...)
@@ -572,18 +570,18 @@ func (s *microPublishStep) SetStatus(status Status) {
 	s.status = status
 }
 
-func (s *microPublishStep) Execute(ctx context.Context, req *Message, opts ...options.Option) (*Message, error) {
+func (s *microPublishStep) Execute(ctx context.Context, req *Message, opts ...ExecuteOption) (*Message, error) {
 	return nil, nil
 }
 
 // NewCallStep create new step with client.Call
-func NewCallStep(service string, name string, method string, opts ...options.Option) Step {
+func NewCallStep(service string, name string, method string, opts ...StepOption) Step {
 	options := NewStepOptions(opts...)
 	return &microCallStep{service: service, method: name + "." + method, opts: options}
 }
 
 // NewPublishStep create new step with client.Publish
-func NewPublishStep(topic string, opts ...options.Option) Step {
+func NewPublishStep(topic string, opts ...StepOption) Step {
 	options := NewStepOptions(opts...)
 	return &microPublishStep{topic: topic, opts: options}
 }

flow/flow.go

@@ -1,5 +1,5 @@
 // Package flow is an interface used for saga pattern microservice workflow
-package flow // import "go.unistack.org/micro/v4/flow"
+package flow // import "go.unistack.org/micro/v3/flow"
 
 import (
 	"context"
@@ -7,8 +7,7 @@ import (
 	"sync"
 	"sync/atomic"
 
-	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v4/options"
+	"go.unistack.org/micro/v3/metadata"
 )
 
 var (
@@ -52,7 +51,7 @@ type Step interface {
 	// Endpoint returns rpc endpoint service_name.service_method or broker topic
 	Endpoint() string
 	// Execute step run
-	Execute(ctx context.Context, req *Message, opts ...options.Option) (*Message, error)
+	Execute(ctx context.Context, req *Message, opts ...ExecuteOption) (*Message, error)
 	// Requires returns dependent steps
 	Requires() []string
 	// Options returns step options
@@ -119,7 +118,7 @@ type Workflow interface {
 	// ID returns id of the workflow
 	ID() string
 	// Execute workflow with args, return execution id and error
-	Execute(ctx context.Context, req *Message, opts ...options.Option) (string, error)
+	Execute(ctx context.Context, req *Message, opts ...ExecuteOption) (string, error)
 	// RemoveSteps remove steps from workflow
 	RemoveSteps(steps ...Step) error
 	// AppendSteps append steps to workflow
@@ -141,7 +140,7 @@ type Flow interface {
 	// Options returns options
 	Options() Options
 	// Init initialize
-	Init(...options.Option) error
+	Init(...Option) error
 	// WorkflowCreate creates new workflow with specific id and steps
 	WorkflowCreate(ctx context.Context, id string, steps ...Step) (Workflow, error)
 	// WorkflowSave saves workflow

flow/flow_test.go

@@ -1,36 +0,0 @@
-package flow
-
-import (
-	"reflect"
-	"testing"
-)
-
-func FuzzMarshall(f *testing.F) {
-	f.Fuzz(func(t *testing.T, ref []byte) {
-		rm := RawMessage(ref)
-
-		b, err := rm.MarshalJSON()
-		if err != nil {
-			t.Errorf("Error MarshalJSON: %s", err)
-		}
-
-		if !reflect.DeepEqual(ref, b) {
-			t.Errorf("Error. Expected '%s', was '%s'", ref, b)
-		}
-	})
-}
-
-func FuzzUnmarshall(f *testing.F) {
-	f.Fuzz(func(t *testing.T, ref string) {
-		b := []byte(ref)
-		rm := RawMessage(b)
-
-		if err := rm.UnmarshalJSON(b); err != nil {
-			t.Errorf("Error UnmarshalJSON: %s", err)
-		}
-
-		if ref != string(rm) {
-			t.Errorf("Error. Expected '%s', was '%s'", ref, rm)
-		}
-	})
-}

flow/options.go

@@ -4,14 +4,16 @@ import (
 	"context"
 	"time"
 
-	"go.unistack.org/micro/v4/client"
-	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v4/store"
-	"go.unistack.org/micro/v4/tracer"
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/store"
+	"go.unistack.org/micro/v3/tracer"
 )
 
+// Option func
+type Option func(*Options)
+
 // Options server struct
 type Options struct {
 	// Context holds the external options and can be used for flow shutdown
@@ -29,7 +31,7 @@ type Options struct {
 }
 
 // NewOptions returns new options struct with default or passed values
-func NewOptions(opts ...options.Option) Options {
+func NewOptions(opts ...Option) Options {
 	options := Options{
 		Context: context.Background(),
 		Logger:  logger.DefaultLogger,
@@ -45,12 +47,66 @@ func NewOptions(opts ...options.Option) Options {
 	return options
 }
 
+// Logger sets the logger option
+func Logger(l logger.Logger) Option {
+	return func(o *Options) {
+		o.Logger = l
+	}
+}
+
+// Meter sets the meter option
+func Meter(m meter.Meter) Option {
+	return func(o *Options) {
+		o.Meter = m
+	}
+}
+
+// Client to use for sync/async communication
+func Client(c client.Client) Option {
+	return func(o *Options) {
+		o.Client = c
+	}
+}
+
+// Context specifies a context for the service.
+// Can be used to signal shutdown of the flow
+// or can be used for extra option values.
+func Context(ctx context.Context) Option {
+	return func(o *Options) {
+		o.Context = ctx
+	}
+}
+
+// Tracer mechanism for distributed tracking
+func Tracer(t tracer.Tracer) Option {
+	return func(o *Options) {
+		o.Tracer = t
+	}
+}
+
+// Store used for intermediate results
+func Store(s store.Store) Option {
+	return func(o *Options) {
+		o.Store = s
+	}
+}
+
+// WorkflowOption func signature
+type WorkflowOption func(*WorkflowOptions)
+
 // WorkflowOptions holds workflow options
 type WorkflowOptions struct {
 	Context context.Context
 	ID      string
 }
 
+// WorkflowID set workflow id
+func WorkflowID(id string) WorkflowOption {
+	return func(o *WorkflowOptions) {
+		o.ID = id
+	}
+}
+
 // ExecuteOptions holds execute options
 type ExecuteOptions struct {
 	// Client holds the client.Client
@@ -73,22 +129,67 @@ type ExecuteOptions struct {
 	Async bool
 }
 
-// Reverse says that dag must be run in reverse order
-func Reverse(b bool) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, b, ".Reverse")
+// ExecuteOption func signature
+type ExecuteOption func(*ExecuteOptions)
+
+// ExecuteClient pass client.Client to ExecuteOption
+func ExecuteClient(c client.Client) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Client = c
 	}
 }
 
-// Async says that caller does not wait for execution complete
-func Async(b bool) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, b, ".Async")
+// ExecuteTracer pass tracer.Tracer to ExecuteOption
+func ExecuteTracer(t tracer.Tracer) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Tracer = t
+	}
+}
+
+// ExecuteLogger pass logger.Logger to ExecuteOption
+func ExecuteLogger(l logger.Logger) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Logger = l
+	}
+}
+
+// ExecuteMeter pass meter.Meter to ExecuteOption
+func ExecuteMeter(m meter.Meter) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Meter = m
+	}
+}
+
+// ExecuteContext pass context.Context ot ExecuteOption
+func ExecuteContext(ctx context.Context) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Context = ctx
+	}
+}
+
+// ExecuteReverse says that dag must be run in reverse order
+func ExecuteReverse(b bool) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Reverse = b
+	}
+}
+
+// ExecuteTimeout pass timeout time.Duration for execution
+func ExecuteTimeout(td time.Duration) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Timeout = td
+	}
+}
+
+// ExecuteAsync says that caller does not wait for execution complete
+func ExecuteAsync(b bool) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Async = b
 	}
 }
 
 // NewExecuteOptions create new ExecuteOptions struct
-func NewExecuteOptions(opts ...options.Option) ExecuteOptions {
+func NewExecuteOptions(opts ...ExecuteOption) ExecuteOptions {
 	options := ExecuteOptions{
 		Client:  client.DefaultClient,
 		Logger:  logger.DefaultLogger,
@@ -110,8 +211,11 @@ type StepOptions struct {
 	Requires []string
 }
 
+// StepOption func signature
+type StepOption func(*StepOptions)
+
 // NewStepOptions create new StepOptions struct
-func NewStepOptions(opts ...options.Option) StepOptions {
+func NewStepOptions(opts ...StepOption) StepOptions {
 	options := StepOptions{
 		Context: context.Background(),
 	}
@@ -121,23 +225,23 @@ func NewStepOptions(opts ...options.Option) StepOptions {
 	return options
 }
 
-// Requires specifies required steps
-func Requires(steps ...string) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, steps, ".Requires")
+// StepID sets the step id for dag
+func StepID(id string) StepOption {
+	return func(o *StepOptions) {
+		o.ID = id
 	}
 }
 
-// Fallback set the step to run on error
-func Fallback(step string) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, step, ".Fallback")
+// StepRequires specifies required steps
+func StepRequires(steps ...string) StepOption {
+	return func(o *StepOptions) {
+		o.Requires = steps
 	}
 }
 
-// ID sets the step ID
-func StepID(id string) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, id, ".ID")
+// StepFallback set the step to run on error
+func StepFallback(step string) StepOption {
+	return func(o *StepOptions) {
+		o.Fallback = step
 	}
 }

fsm/fsm.go

@@ -1,4 +1,4 @@
-package fsm // import "go.unistack.org/micro/v4/fsm"
+package fsm // import "go.unistack.org/micro/v3/fsm"
 
 import (
 	"context"

fsm/fsm_test.go

@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"testing"
 
-	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v3/logger"
 )
 
 func TestFSMStart(t *testing.T) {
@@ -17,7 +17,7 @@ func TestFSMStart(t *testing.T) {
 
 	wrapper := func(next StateFunc) StateFunc {
 		return func(sctx context.Context, s State, opts ...StateOption) (State, error) {
-			sctx = logger.NewContext(sctx, logger.Attrs("state", s.Name()))
+			sctx = logger.NewContext(sctx, logger.Fields("state", s.Name()))
 			return next(sctx, s, opts...)
 		}
 	}

go.mod

@@ -1,20 +1,20 @@
-module go.unistack.org/micro/v4
+module go.unistack.org/micro/v3
 
 go 1.20
 
 require (
 	dario.cat/mergo v1.0.0
 	github.com/DATA-DOG/go-sqlmock v1.5.0
-	github.com/google/uuid v1.6.0
+	github.com/google/uuid v1.3.0
 	github.com/patrickmn/go-cache v2.1.0+incompatible
 	github.com/silas/dag v0.0.0-20220518035006-a7e85ada93c5
-	golang.org/x/sync v0.6.0
-	golang.org/x/sys v0.16.0
-	google.golang.org/grpc v1.62.1
-	google.golang.org/protobuf v1.32.0
+	golang.org/x/sync v0.3.0
+	google.golang.org/grpc v1.57.0
+	google.golang.org/protobuf v1.31.0
 )
 
 require (
 	github.com/golang/protobuf v1.5.3 // indirect
-	google.golang.org/genproto/googleapis/rpc v0.0.0-20240123012728-ef4313101c80 // indirect
+	golang.org/x/net v0.14.0 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20230526203410-71b5a4ffd15e // indirect
 )

go.sum

@@ -6,28 +6,28 @@ github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaS
 github.com/golang/protobuf v1.5.3 h1:KhyjKVUg7Usr/dYsdSqoFveMYd5ko72D+zANwlG1mmg=
 github.com/golang/protobuf v1.5.3/go.mod h1:XVQd3VNwM+JqD3oG2Ue2ip4fOMUkwXdXDdiuN0vRsmY=
 github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
-github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
-github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
-github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
+github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
+github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/patrickmn/go-cache v2.1.0+incompatible h1:HRMgzkcYKYpi3C8ajMPV8OFXaaRUnok+kx1WdO15EQc=
 github.com/patrickmn/go-cache v2.1.0+incompatible/go.mod h1:3Qf8kWWT7OJRJbdiICTKqZju1ZixQ/KpMGzzAfe6+WQ=
 github.com/silas/dag v0.0.0-20220518035006-a7e85ada93c5 h1:G/FZtUu7a6NTWl3KUHMV9jkLAh/Rvtf03NWMHaEDl+E=
 github.com/silas/dag v0.0.0-20220518035006-a7e85ada93c5/go.mod h1:7RTUFBdIRC9nZ7/3RyRNH1bdqIShrDejd1YbLwgPS+I=
-golang.org/x/net v0.20.0 h1:aCL9BSgETF1k+blQaYUBx9hJ9LOGP3gAVemcZlf1Kpo=
-golang.org/x/sync v0.6.0 h1:5BMeUDZ7vkXGfEr1x9B4bRcTH4lpkTkpdh0T/J+qjbQ=
-golang.org/x/sync v0.6.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
-golang.org/x/sys v0.16.0 h1:xWw16ngr6ZMtmxDyKyIgsE93KNKz5HKmMa3b8ALHidU=
-golang.org/x/sys v0.16.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
-golang.org/x/text v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
+golang.org/x/net v0.14.0 h1:BONx9s002vGdD9umnlX1Po8vOZmrgH34qlHcD1MfK14=
+golang.org/x/net v0.14.0/go.mod h1:PpSgVXXLK0OxS0F31C1/tv6XNguvCrnXIDrFMspZIUI=
+golang.org/x/sync v0.3.0 h1:ftCYgMx6zT/asHUrPw8BLLscYtGznsLAnjq5RH9P66E=
+golang.org/x/sync v0.3.0/go.mod h1:FU7BRWz2tNW+3quACPkgCx/L+uEAv1htQ0V83Z9Rj+Y=
+golang.org/x/sys v0.11.0 h1:eG7RXZHdqOJ1i+0lgLgCpSXAp6M3LYlAo6osgSi0xOM=
+golang.org/x/text v0.12.0 h1:k+n5B8goJNdU7hSvEtMUz3d1Q6D/XW4COJSJR6fN0mc=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20240123012728-ef4313101c80 h1:AjyfHzEPEFp/NpvfN5g+KDla3EMojjhRVZc1i7cj+oM=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20240123012728-ef4313101c80/go.mod h1:PAREbraiVEVGVdTZsVWjSbbTtSyGbAgIIvni8a8CD5s=
-google.golang.org/grpc v1.62.1 h1:B4n+nfKzOICUXMgyrNd19h/I9oH0L1pizfk1d4zSgTk=
-google.golang.org/grpc v1.62.1/go.mod h1:IWTG0VlJLCh1SkC58F7np9ka9mx/WNkjl4PGJaiq+QE=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20230526203410-71b5a4ffd15e h1:NumxXLPfHSndr3wBBdeKiVHjGVFzi9RX2HwwQke94iY=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20230526203410-71b5a4ffd15e/go.mod h1:66JfowdXAEgad5O9NnYcsNPLCPZJD++2L9X0PCMODrA=
+google.golang.org/grpc v1.57.0 h1:kfzNeI/klCGD2YPMUlaGNT3pxvYfga7smW3Vth8Zsiw=
+google.golang.org/grpc v1.57.0/go.mod h1:Sd+9RMTACXwmub0zcNY2c4arhtrbBYD1AUHI/dt16Mo=
 google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
 google.golang.org/protobuf v1.26.0/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQnmE0givc=
-google.golang.org/protobuf v1.32.0 h1:pPC6BG5ex8PDFnkbrGU3EixyhKcQ2aDuBS36lqK/C7I=
-google.golang.org/protobuf v1.32.0/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
+google.golang.org/protobuf v1.31.0 h1:g0LDEJHgrBl9N9r17Ru3sqWhkIx2NB67okBHPwC7hs8=
+google.golang.org/protobuf v1.31.0/go.mod h1:HV8QOd/L58Z+nl8r43ehVNZIU/HEI6OcFqwMG9pJV4I=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

logger/context.go

@@ -20,3 +20,13 @@ func NewContext(ctx context.Context, l Logger) context.Context {
 	}
 	return context.WithValue(ctx, loggerKey{}, l)
 }
+
+// SetOption returns a function to setup a context with given value
+func SetOption(k, v interface{}) Option {
+	return func(o *Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}

logger/context_test.go

@@ -40,3 +40,14 @@ func TestNewContext(t *testing.T) {
 		t.Fatal("NewContext not works")
 	}
 }
+
+func TestSetOption(t *testing.T) {
+	type key struct{}
+	o := SetOption(key{}, "test")
+	opts := &Options{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetOption not works")
+	}
+}

logger/logger.go

@@ -1,10 +1,9 @@
 // Package logger provides a log interface
-package logger
+package logger // import "go.unistack.org/micro/v3/logger"
 
 import (
 	"context"
-
-	"go.unistack.org/micro/v4/options"
+	"os"
 )
 
 type ContextAttrFunc func(ctx context.Context) []interface{}
@@ -13,7 +12,7 @@ var DefaultContextAttrFuncs []ContextAttrFunc
 
 var (
 	// DefaultLogger variable
-	DefaultLogger = NewLogger()
+	DefaultLogger = NewLogger(WithLevel(ParseLevel(os.Getenv("MICRO_LOG_LEVEL"))))
 	// DefaultLevel used by logger
 	DefaultLevel = InfoLevel
 	// DefaultCallerSkipCount used by logger
@@ -23,78 +22,155 @@ var (
 // Logger is a generic logging interface
 type Logger interface {
 	// Init initialises options
-	Init(opts ...options.Option) error
+	Init(opts ...Option) error
 	// Clone create logger copy with new options
-	Clone(opts ...options.Option) Logger
+	Clone(opts ...Option) Logger
 	// V compare provided verbosity level with current log level
 	V(level Level) bool
 	// Level sets the log level for logger
 	Level(level Level)
 	// The Logger options
 	Options() Options
-	// Attrs set attrs to always be logged with keyval pairs
-	Attrs(attrs ...interface{}) Logger
+	// Fields set fields to always be logged with keyval pairs
+	Fields(fields ...interface{}) Logger
 	// Info level message
-	Info(ctx context.Context, msg string, attrs ...interface{})
-	// Tracef level message
-	Trace(ctx context.Context, msg string, attrs ...interface{})
+	Info(ctx context.Context, args ...interface{})
+	// Trace level message
+	Trace(ctx context.Context, args ...interface{})
 	// Debug level message
-	Debug(ctx context.Context, msg string, attrs ...interface{})
+	Debug(ctx context.Context, args ...interface{})
 	// Warn level message
-	Warn(ctx context.Context, msg string, attrs ...interface{})
+	Warn(ctx context.Context, args ...interface{})
 	// Error level message
-	Error(ctx context.Context, msg string, attrs ...interface{})
+	Error(ctx context.Context, args ...interface{})
 	// Fatal level message
-	Fatal(ctx context.Context, msg string, attrs ...interface{})
+	Fatal(ctx context.Context, args ...interface{})
+	// Infof level message
+	Infof(ctx context.Context, msg string, args ...interface{})
+	// Tracef level message
+	Tracef(ctx context.Context, msg string, args ...interface{})
+	// Debug level message
+	Debugf(ctx context.Context, msg string, args ...interface{})
+	// Warn level message
+	Warnf(ctx context.Context, msg string, args ...interface{})
+	// Error level message
+	Errorf(ctx context.Context, msg string, args ...interface{})
+	// Fatal level message
+	Fatalf(ctx context.Context, msg string, args ...interface{})
 	// Log logs message with needed level
-	Log(ctx context.Context, level Level, msg string, attrs ...interface{})
-	// String returns the type name of logger
-	String() string
-	// String returns the name of logger
+	Log(ctx context.Context, level Level, args ...interface{})
+	// Logf logs message with needed level
+	Logf(ctx context.Context, level Level, msg string, args ...interface{})
+	// Name returns broker instance name
 	Name() string
+	// String returns the type of logger
+	String() string
 }
 
-// Info writes formatted msg to default logger on info level
-func Info(ctx context.Context, msg string, attrs ...interface{}) {
-	DefaultLogger.Info(ctx, msg, attrs...)
+// Field contains keyval pair
+type Field interface{}
+
+// Info writes msg to default logger on info level
+//
+// Deprecated: Dont use logger methods directly, use instance of logger to avoid additional allocations
+func Info(ctx context.Context, args ...interface{}) {
+	DefaultLogger.Clone(WithCallerSkipCount(DefaultCallerSkipCount+1)).Info(ctx, args...)
 }
 
-// Error writes formatted msg to default logger on error level
-func Error(ctx context.Context, msg string, attrs ...interface{}) {
-	DefaultLogger.Error(ctx, msg, attrs...)
+// Error writes msg to default logger on error level
+//
+// Deprecated: Dont use logger methods directly, use instance of logger to avoid additional allocations
+func Error(ctx context.Context, args ...interface{}) {
+	DefaultLogger.Clone(WithCallerSkipCount(DefaultCallerSkipCount+1)).Error(ctx, args...)
 }
 
-// Debug writes formatted msg to default logger on debug level
-func Debug(ctx context.Context, msg string, attrs ...interface{}) {
-	DefaultLogger.Debug(ctx, msg, attrs...)
+// Debug writes msg to default logger on debug level
+//
+// Deprecated: Dont use logger methods directly, use instance of logger to avoid additional allocations
+func Debug(ctx context.Context, args ...interface{}) {
+	DefaultLogger.Clone(WithCallerSkipCount(DefaultCallerSkipCount+1)).Debug(ctx, args...)
 }
 
-// Warn writes formatted msg to default logger on warn level
-func Warn(ctx context.Context, msg string, attrs ...interface{}) {
-	DefaultLogger.Warn(ctx, msg, attrs...)
+// Warn writes msg to default logger on warn level
+//
+// Deprecated: Dont use logger methods directly, use instance of logger to avoid additional allocations
+func Warn(ctx context.Context, args ...interface{}) {
+	DefaultLogger.Clone(WithCallerSkipCount(DefaultCallerSkipCount+1)).Warn(ctx, args...)
 }
 
-// Trace writes formatted msg to default logger on trace level
-func Trace(ctx context.Context, msg string, attrs ...interface{}) {
-	DefaultLogger.Trace(ctx, msg, attrs...)
+// Trace writes msg to default logger on trace level
+//
+// Deprecated: Dont use logger methods directly, use instance of logger to avoid additional allocations
+func Trace(ctx context.Context, args ...interface{}) {
+	DefaultLogger.Clone(WithCallerSkipCount(DefaultCallerSkipCount+1)).Trace(ctx, args...)
 }
 
-// Fatal writes formatted msg to default logger on fatal level
-func Fatal(ctx context.Context, msg string, attrs ...interface{}) {
-	DefaultLogger.Fatal(ctx, msg, attrs...)
+// Fatal writes msg to default logger on fatal level
+//
+// Deprecated: Dont use logger methods directly, use instance of logger to avoid additional allocations
+func Fatal(ctx context.Context, args ...interface{}) {
+	DefaultLogger.Clone(WithCallerSkipCount(DefaultCallerSkipCount+1)).Fatal(ctx, args...)
+}
+
+// Infof writes formatted msg to default logger on info level
+//
+// Deprecated: Dont use logger methods directly, use instance of logger to avoid additional allocations
+func Infof(ctx context.Context, msg string, args ...interface{}) {
+	DefaultLogger.Clone(WithCallerSkipCount(DefaultCallerSkipCount+1)).Infof(ctx, msg, args...)
+}
+
+// Errorf writes formatted msg to default logger on error level
+//
+// Deprecated: Dont use logger methods directly, use instance of logger to avoid additional allocations
+func Errorf(ctx context.Context, msg string, args ...interface{}) {
+	DefaultLogger.Clone(WithCallerSkipCount(DefaultCallerSkipCount+1)).Errorf(ctx, msg, args...)
+}
+
+// Debugf writes formatted msg to default logger on debug level
+//
+// Deprecated: Dont use logger methods directly, use instance of logger to avoid additional allocations
+func Debugf(ctx context.Context, msg string, args ...interface{}) {
+	DefaultLogger.Clone(WithCallerSkipCount(DefaultCallerSkipCount+1)).Debugf(ctx, msg, args...)
+}
+
+// Warnf writes formatted msg to default logger on warn level
+//
+// Deprecated: Dont use logger methods directly, use instance of logger to avoid additional allocations
+func Warnf(ctx context.Context, msg string, args ...interface{}) {
+	DefaultLogger.Clone(WithCallerSkipCount(DefaultCallerSkipCount+1)).Warnf(ctx, msg, args...)
+}
+
+// Tracef writes formatted msg to default logger on trace level
+//
+// Deprecated: Dont use logger methods directly, use instance of logger to avoid additional allocations
+func Tracef(ctx context.Context, msg string, args ...interface{}) {
+	DefaultLogger.Clone(WithCallerSkipCount(DefaultCallerSkipCount+1)).Tracef(ctx, msg, args...)
+}
+
+// Fatalf writes formatted msg to default logger on fatal level
+//
+// Deprecated: Dont use logger methods directly, use instance of logger to avoid additional allocations
+func Fatalf(ctx context.Context, msg string, args ...interface{}) {
+	DefaultLogger.Clone(WithCallerSkipCount(DefaultCallerSkipCount+1)).Fatalf(ctx, msg, args...)
 }
 
 // V returns true if passed level enabled in default logger
+//
+// Deprecated: Dont use logger methods directly, use instance of logger to avoid additional allocations
 func V(level Level) bool {
 	return DefaultLogger.V(level)
 }
 
-// Init initialize default logger
-func Init(opts ...options.Option) error {
+// Init initialize logger
+//
+// Deprecated: Dont use logger methods directly, use instance of logger to avoid additional allocations
+func Init(opts ...Option) error {
 	return DefaultLogger.Init(opts...)
 }
 
-// Attrs create default logger with specific attrs
-func Attrs(attrs ...interface{}) Logger {
-	return DefaultLogger.Attrs(attrs...)
+// Fields create logger with specific fields
+//
+// Deprecated: Dont use logger methods directly, use instance of logger to avoid additional allocations
+func Fields(fields ...interface{}) Logger {
+	return DefaultLogger.Fields(fields...)
 }

logger/noop.go

@@ -2,34 +2,36 @@ package logger
 
 import (
 	"context"
-
-	"go.unistack.org/micro/v4/options"
 )
 
 type noopLogger struct {
 	opts Options
 }
 
-func NewLogger(opts ...options.Option) Logger {
+func NewLogger(opts ...Option) Logger {
 	options := NewOptions(opts...)
 	return &noopLogger{opts: options}
 }
 
-func (l *noopLogger) V(lvl Level) bool {
+func (l *noopLogger) V(_ Level) bool {
 	return false
 }
 
-func (l *noopLogger) Level(lvl Level) {
+func (l *noopLogger) Level(_ Level) {
 }
 
-func (l *noopLogger) Init(opts ...options.Option) error {
+func (l *noopLogger) Name() string {
+	return l.opts.Name
+}
+
+func (l *noopLogger) Init(opts ...Option) error {
 	for _, o := range opts {
 		o(&l.opts)
 	}
 	return nil
 }
 
-func (l *noopLogger) Clone(opts ...options.Option) Logger {
+func (l *noopLogger) Clone(opts ...Option) Logger {
 	nl := &noopLogger{opts: l.opts}
 	for _, o := range opts {
 		o(&nl.opts)
@@ -37,7 +39,7 @@ func (l *noopLogger) Clone(opts ...options.Option) Logger {
 	return nl
 }
 
-func (l *noopLogger) Attrs(attrs ...interface{}) Logger {
+func (l *noopLogger) Fields(_ ...interface{}) Logger {
 	return l
 }
 
@@ -45,31 +47,48 @@ func (l *noopLogger) Options() Options {
 	return l.opts
 }
 
-func (l *noopLogger) Name() string {
-	return l.opts.Name
-}
-
 func (l *noopLogger) String() string {
 	return "noop"
 }
 
-func (l *noopLogger) Log(ctx context.Context, lvl Level, msg string, attrs ...interface{}) {
+func (l *noopLogger) Log(ctx context.Context, lvl Level, attrs ...interface{}) {
 }
 
-func (l *noopLogger) Info(ctx context.Context, msg string, attrs ...interface{}) {
+func (l *noopLogger) Info(ctx context.Context, attrs ...interface{}) {
 }
 
-func (l *noopLogger) Debug(ctx context.Context, msg string, attrs ...interface{}) {
+func (l *noopLogger) Debug(ctx context.Context, attrs ...interface{}) {
 }
 
-func (l *noopLogger) Error(ctx context.Context, msg string, attrs ...interface{}) {
+func (l *noopLogger) Error(ctx context.Context, attrs ...interface{}) {
 }
 
-func (l *noopLogger) Trace(ctx context.Context, msg string, attrs ...interface{}) {
+func (l *noopLogger) Trace(ctx context.Context, attrs ...interface{}) {
 }
 
-func (l *noopLogger) Warn(ctx context.Context, msg string, attrs ...interface{}) {
+func (l *noopLogger) Warn(ctx context.Context, attrs ...interface{}) {
 }
 
-func (l *noopLogger) Fatal(ctx context.Context, msg string, attrs ...interface{}) {
+func (l *noopLogger) Fatal(ctx context.Context, attrs ...interface{}) {
+}
+
+func (l *noopLogger) Logf(ctx context.Context, lvl Level, msg string, attrs ...interface{}) {
+}
+
+func (l *noopLogger) Infof(ctx context.Context, msg string, attrs ...interface{}) {
+}
+
+func (l *noopLogger) Debugf(ctx context.Context, msg string, attrs ...interface{}) {
+}
+
+func (l *noopLogger) Errorf(ctx context.Context, msg string, attrs ...interface{}) {
+}
+
+func (l *noopLogger) Tracef(ctx context.Context, msg string, attrs ...interface{}) {
+}
+
+func (l *noopLogger) Warnf(ctx context.Context, msg string, attrs ...interface{}) {
+}
+
+func (l *noopLogger) Fatalf(ctx context.Context, msg string, attrs ...interface{}) {
 }

logger/options.go

@@ -5,239 +5,170 @@ import (
 	"io"
 	"log/slog"
 	"os"
-	"reflect"
-	"time"
-
-	"go.unistack.org/micro/v4/options"
-	rutil "go.unistack.org/micro/v4/util/reflect"
 )
 
+// Option func signature
+type Option func(*Options)
+
 // Options holds logger options
 type Options struct {
 	// Out holds the output writer
 	Out io.Writer
 	// Context holds exernal options
 	Context context.Context
-	// TimeFunc used to obtain current time
-	TimeFunc func() time.Time
-	// TimeKey is the key used for the time of the log call
-	TimeKey string
 	// Name holds the logger name
 	Name string
+	// Fields holds additional metadata
+	Fields []interface{}
+
+	// CallerSkipCount number of frmaes to skip
+	CallerSkipCount int
+	// ContextAttrFuncs contains funcs that executed before log func on context
+	ContextAttrFuncs []ContextAttrFunc
+	// TimeKey is the key used for the time of the log call
+	TimeKey string
 	// LevelKey is the key used for the level of the log call
 	LevelKey string
+	// ErroreKey is the key used for the error of the log call
+	ErrorKey string
 	// MessageKey is the key used for the message of the log call
 	MessageKey string
-	// ErrorKey is the key used for the error info
-	ErrorKey string
 	// SourceKey is the key used for the source file and line of the log call
 	SourceKey string
 	// StacktraceKey is the key used for the stacktrace
 	StacktraceKey string
-	// Attrs holds additional attributes
-	Attrs []interface{}
-	// ContextAttrFuncs contains funcs that executed before log func on context
-	ContextAttrFuncs []ContextAttrFunc
-	// CallerSkipCount number of frmaes to skip
-	CallerSkipCount int
-	// The logging level the logger should log
-	Level Level
 	// AddStacktrace controls writing of stacktaces on error
 	AddStacktrace bool
 	// AddSource enabled writing source file and position in log
 	AddSource bool
+	// The logging level the logger should log
+	Level Level
 }
 
 // NewOptions creates new options struct
-func NewOptions(opts ...options.Option) Options {
+func NewOptions(opts ...Option) Options {
 	options := Options{
 		Level:            DefaultLevel,
-		Attrs:            make([]interface{}, 0, 6),
+		Fields:           make([]interface{}, 0, 6),
 		Out:              os.Stderr,
 		CallerSkipCount:  DefaultCallerSkipCount,
 		Context:          context.Background(),
 		ContextAttrFuncs: DefaultContextAttrFuncs,
 		AddSource:        true,
-		TimeFunc:         time.Now,
 	}
 
-	_ = WithMicroKeys()(&options)
+	WithMicroKeys()(&options)
 
 	for _, o := range opts {
-		_ = o(&options)
+		o(&options)
 	}
+
 	return options
 }
 
 // WithContextAttrFuncs appends default funcs for the context arrts filler
-func WithContextAttrFuncs(fncs ...ContextAttrFunc) options.Option {
-	return func(src interface{}) error {
-		v, err := options.Get(src, ".ContextAttrFuncs")
-		if err != nil {
-			return err
-		} else if rutil.IsZero(v) {
-			v = reflect.MakeSlice(reflect.TypeOf(v), 0, len(fncs)).Interface()
-		}
-		cv := reflect.ValueOf(v)
-		for _, l := range fncs {
-			cv = reflect.Append(cv, reflect.ValueOf(l))
-		}
-		return options.Set(src, cv.Interface(), ".ContextAttrFuncs")
+func WithContextAttrFuncs(fncs ...ContextAttrFunc) Option {
+	return func(o *Options) {
+		o.ContextAttrFuncs = append(o.ContextAttrFuncs, fncs...)
 	}
 }
 
-// WithAttrs set default fields for the logger
-func WithAttrs(attrs ...interface{}) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, attrs, ".Attrs")
+// WithFields set default fields for the logger
+func WithFields(fields ...interface{}) Option {
+	return func(o *Options) {
+		o.Fields = fields
 	}
 }
 
 // WithLevel set default level for the logger
-func WithLevel(lvl Level) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, lvl, ".Level")
+func WithLevel(level Level) Option {
+	return func(o *Options) {
+		o.Level = level
 	}
 }
 
 // WithOutput set default output writer for the logger
-func WithOutput(out io.Writer) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, out, ".Out")
+func WithOutput(out io.Writer) Option {
+	return func(o *Options) {
+		o.Out = out
 	}
 }
 
-// WithCallerSkipCount set frame count to skip
-func WithCallerSkipCount(c int) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, c, ".CallerSkipCount")
-	}
-}
-
-func WithZapKeys() options.Option {
-	return func(src interface{}) error {
-		var err error
-		if err = options.Set(src, "@timestamp", ".TimeKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "level", ".LevelKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "msg", ".MessageKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "caller", ".SourceKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "stacktrace", ".StacktraceKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "error", ".ErrorKey"); err != nil {
-			return err
-		}
-		return nil
-	}
-}
-
-func WithZerologKeys() options.Option {
-	return func(src interface{}) error {
-		var err error
-		if err = options.Set(src, "time", ".TimeKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "level", ".LevelKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "message", ".MessageKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "caller", ".SourceKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "stacktrace", ".StacktraceKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "error", ".ErrorKey"); err != nil {
-			return err
-		}
-		return nil
-	}
-}
-
-func WithSlogKeys() options.Option {
-	return func(src interface{}) error {
-		var err error
-		if err = options.Set(src, slog.TimeKey, ".TimeKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, slog.LevelKey, ".LevelKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, slog.MessageKey, ".MessageKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, slog.SourceKey, ".SourceKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "stacktrace", ".StacktraceKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "error", ".ErrorKey"); err != nil {
-			return err
-		}
-		return nil
-	}
-}
-
-func WithMicroKeys() options.Option {
-	return func(src interface{}) error {
-		var err error
-		if err = options.Set(src, "timestamp", ".TimeKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "level", ".LevelKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "msg", ".MessageKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "caller", ".SourceKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "stacktrace", ".StacktraceKey"); err != nil {
-			return err
-		}
-		if err = options.Set(src, "error", ".ErrorKey"); err != nil {
-			return err
-		}
-		return nil
-	}
-}
-
-// WithAddCallerSkipCount add skip count for copy logger
-func WithAddCallerSkipCount(n int) options.Option {
-	return func(src interface{}) error {
-		c, err := options.Get(src, ".CallerSkipCount")
-		if err != nil {
-			return err
-		}
-		if err = options.Set(src, c.(int)+n, ".CallerSkipCount"); err != nil {
-			return err
-		}
-		return nil
-	}
-}
-
-// WithAddStacktrace controls writing stacktrace on error
-func WithAddStacktrace(v bool) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, v, ".AddStacktrace")
+// WitAddStacktrace controls writing stacktrace on error
+func WithAddStacktrace(v bool) Option {
+	return func(o *Options) {
+		o.AddStacktrace = v
 	}
 }
 
 // WitAddSource controls writing source file and pos in log
-func WithAddSource(v bool) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, v, ".AddSource")
+func WithAddSource(v bool) Option {
+	return func(o *Options) {
+		o.AddSource = v
+	}
+}
+
+// WithCallerSkipCount set frame count to skip
+func WithCallerSkipCount(c int) Option {
+	return func(o *Options) {
+		o.CallerSkipCount = c
+	}
+}
+
+// WithContext set context
+func WithContext(ctx context.Context) Option {
+	return func(o *Options) {
+		o.Context = ctx
+	}
+}
+
+// WithName sets the name
+func WithName(n string) Option {
+	return func(o *Options) {
+		o.Name = n
+	}
+}
+
+func WithZapKeys() Option {
+	return func(o *Options) {
+		o.TimeKey = "@timestamp"
+		o.LevelKey = "level"
+		o.MessageKey = "msg"
+		o.SourceKey = "caller"
+		o.StacktraceKey = "stacktrace"
+		o.ErrorKey = "error"
+	}
+}
+
+func WithZerologKeys() Option {
+	return func(o *Options) {
+		o.TimeKey = "time"
+		o.LevelKey = "level"
+		o.MessageKey = "message"
+		o.SourceKey = "caller"
+		o.StacktraceKey = "stacktrace"
+		o.ErrorKey = "error"
+	}
+}
+
+func WithSlogKeys() Option {
+	return func(o *Options) {
+		o.TimeKey = slog.TimeKey
+		o.LevelKey = slog.LevelKey
+		o.MessageKey = slog.MessageKey
+		o.SourceKey = slog.SourceKey
+		o.StacktraceKey = "stacktrace"
+		o.ErrorKey = "error"
+	}
+}
+
+func WithMicroKeys() Option {
+	return func(o *Options) {
+		o.TimeKey = "timestamp"
+		o.LevelKey = "level"
+		o.MessageKey = "msg"
+		o.SourceKey = "caller"
+		o.StacktraceKey = "stacktrace"
+		o.ErrorKey = "error"
 	}
 }

logger/slog/slog.go

@@ -2,16 +2,17 @@ package slog
 
 import (
 	"context"
+	"fmt"
 	"log/slog"
 	"os"
 	"regexp"
 	"runtime"
 	"strconv"
 	"sync"
+	"time"
 
-	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v4/tracer"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 var reTrace = regexp.MustCompile(`.*/slog/logger\.go.*\n`)
@@ -61,19 +62,18 @@ func (s *slogLogger) renameAttr(_ []string, a slog.Attr) slog.Attr {
 }
 
 type slogLogger struct {
+	slog    *slog.Logger
 	leveler *slog.LevelVar
-	handler slog.Handler
 	opts    logger.Options
 	mu      sync.RWMutex
 }
 
-func (s *slogLogger) Clone(opts ...options.Option) logger.Logger {
+func (s *slogLogger) Clone(opts ...logger.Option) logger.Logger {
 	s.mu.RLock()
 	options := s.opts
-	s.mu.RUnlock()
 
 	for _, o := range opts {
-		_ = o(&options)
+		o(&options)
 	}
 
 	l := &slogLogger{
@@ -87,7 +87,10 @@ func (s *slogLogger) Clone(opts ...options.Option) logger.Logger {
 		AddSource:   l.opts.AddSource,
 	}
 	l.leveler.Set(loggerToSlogLevel(l.opts.Level))
-	l.handler = slog.New(slog.NewJSONHandler(options.Out, handleOpt)).With(options.Attrs...).Handler()
+	handler := slog.NewJSONHandler(options.Out, handleOpt)
+	l.slog = slog.New(handler).With(options.Fields...)
+
+	s.mu.RUnlock()
 
 	return l
 }
@@ -104,15 +107,11 @@ func (s *slogLogger) Options() logger.Options {
 	return s.opts
 }
 
-func (s *slogLogger) Attrs(attrs ...interface{}) logger.Logger {
+func (s *slogLogger) Fields(attrs ...interface{}) logger.Logger {
 	s.mu.RLock()
-	level := s.leveler.Level()
-	options := s.opts
-	s.mu.RUnlock()
-
-	l := &slogLogger{opts: options}
+	l := &slogLogger{opts: s.opts}
 	l.leveler = new(slog.LevelVar)
-	l.leveler.Set(level)
+	l.leveler.Set(s.leveler.Level())
 
 	handleOpt := &slog.HandlerOptions{
 		ReplaceAttr: l.renameAttr,
@@ -120,12 +119,15 @@ func (s *slogLogger) Attrs(attrs ...interface{}) logger.Logger {
 		AddSource:   l.opts.AddSource,
 	}
 
-	l.handler = slog.New(slog.NewJSONHandler(s.opts.Out, handleOpt)).With(attrs...).Handler()
+	handler := slog.NewJSONHandler(s.opts.Out, handleOpt)
+	l.slog = slog.New(handler).With(attrs...)
+
+	s.mu.RUnlock()
 
 	return l
 }
 
-func (s *slogLogger) Init(opts ...options.Option) error {
+func (s *slogLogger) Init(opts ...logger.Option) error {
 	s.mu.Lock()
 
 	if len(s.opts.ContextAttrFuncs) == 0 {
@@ -133,9 +135,7 @@ func (s *slogLogger) Init(opts ...options.Option) error {
 	}
 
 	for _, o := range opts {
-		if err := o(&s.opts); err != nil {
-			return err
-		}
+		o(&s.opts)
 	}
 
 	s.leveler = new(slog.LevelVar)
@@ -145,22 +145,25 @@ func (s *slogLogger) Init(opts ...options.Option) error {
 		AddSource:   s.opts.AddSource,
 	}
 	s.leveler.Set(loggerToSlogLevel(s.opts.Level))
-	s.handler = slog.New(slog.NewJSONHandler(s.opts.Out, handleOpt)).With(s.opts.Attrs...).Handler()
+	handler := slog.NewJSONHandler(s.opts.Out, handleOpt)
+	s.slog = slog.New(handler).With(s.opts.Fields...)
+
 	s.mu.Unlock()
 
 	return nil
 }
 
-func (s *slogLogger) Log(ctx context.Context, lvl logger.Level, msg string, attrs ...interface{}) {
+func (s *slogLogger) Log(ctx context.Context, lvl logger.Level, attrs ...interface{}) {
 	if !s.V(lvl) {
 		return
 	}
 	var pcs [1]uintptr
 	runtime.Callers(s.opts.CallerSkipCount, pcs[:]) // skip [Callers, Infof]
-	r := slog.NewRecord(s.opts.TimeFunc(), loggerToSlogLevel(lvl), msg, pcs[0])
+	r := slog.NewRecord(time.Now(), loggerToSlogLevel(lvl), fmt.Sprintf("%s", attrs[0]), pcs[0])
 	for _, fn := range s.opts.ContextAttrFuncs {
 		attrs = append(attrs, fn(ctx)...)
 	}
+
 	for idx, attr := range attrs {
 		if ve, ok := attr.(error); ok && ve != nil {
 			attrs[idx] = slog.String(s.opts.ErrorKey, ve.Error())
@@ -176,7 +179,7 @@ func (s *slogLogger) Log(ctx context.Context, lvl logger.Level, msg string, attr
 			}
 		}
 	}
-	r.Add(attrs...)
+	r.Add(attrs[1:]...)
 	r.Attrs(func(a slog.Attr) bool {
 		if a.Key == s.opts.ErrorKey {
 			if span, ok := tracer.SpanFromContext(ctx); ok {
@@ -186,19 +189,80 @@ func (s *slogLogger) Log(ctx context.Context, lvl logger.Level, msg string, attr
 		}
 		return true
 	})
-	_ = s.handler.Handle(ctx, r)
+	_ = s.slog.Handler().Handle(ctx, r)
 }
 
-func (s *slogLogger) Info(ctx context.Context, msg string, attrs ...interface{}) {
+func (s *slogLogger) Logf(ctx context.Context, lvl logger.Level, msg string, attrs ...interface{}) {
+	if !s.V(lvl) {
+		return
+	}
+	var pcs [1]uintptr
+	runtime.Callers(s.opts.CallerSkipCount, pcs[:]) // skip [Callers, Infof]
+	r := slog.NewRecord(time.Now(), loggerToSlogLevel(lvl), msg, pcs[0])
+	for _, fn := range s.opts.ContextAttrFuncs {
+		attrs = append(attrs, fn(ctx)...)
+	}
+
+	for idx, attr := range attrs {
+		if ve, ok := attr.(error); ok && ve != nil {
+			attrs[idx] = slog.String(s.opts.ErrorKey, ve.Error())
+			break
+		}
+	}
+	if s.opts.AddStacktrace && lvl == logger.ErrorLevel {
+		stackInfo := make([]byte, 1024*1024)
+		if stackSize := runtime.Stack(stackInfo, false); stackSize > 0 {
+			traceLines := reTrace.Split(string(stackInfo[:stackSize]), -1)
+			if len(traceLines) != 0 {
+				attrs = append(attrs, (slog.String(s.opts.StacktraceKey, traceLines[len(traceLines)-1])))
+			}
+		}
+	}
+	r.Add(attrs[1:]...)
+	r.Attrs(func(a slog.Attr) bool {
+		if a.Key == s.opts.ErrorKey {
+			if span, ok := tracer.SpanFromContext(ctx); ok {
+				span.SetStatus(tracer.SpanStatusError, a.Value.String())
+				return false
+			}
+		}
+		return true
+	})
+	_ = s.slog.Handler().Handle(ctx, r)
+}
+
+func (s *slogLogger) Info(ctx context.Context, attrs ...interface{}) {
 	if !s.V(logger.InfoLevel) {
 		return
 	}
 	var pcs [1]uintptr
 	runtime.Callers(s.opts.CallerSkipCount, pcs[:]) // skip [Callers, Infof]
-	r := slog.NewRecord(s.opts.TimeFunc(), slog.LevelInfo, msg, pcs[0])
+	r := slog.NewRecord(time.Now(), slog.LevelInfo, fmt.Sprintf("%s", attrs[0]), pcs[0])
 	for _, fn := range s.opts.ContextAttrFuncs {
 		attrs = append(attrs, fn(ctx)...)
 	}
+
+	for idx, attr := range attrs {
+		if ve, ok := attr.(error); ok && ve != nil {
+			attrs[idx] = slog.String(s.opts.ErrorKey, ve.Error())
+			break
+		}
+	}
+	r.Add(attrs[1:]...)
+	_ = s.slog.Handler().Handle(ctx, r)
+}
+
+func (s *slogLogger) Infof(ctx context.Context, msg string, attrs ...interface{}) {
+	if !s.V(logger.InfoLevel) {
+		return
+	}
+	var pcs [1]uintptr
+	runtime.Callers(s.opts.CallerSkipCount, pcs[:]) // skip [Callers, Infof]
+	r := slog.NewRecord(time.Now(), slog.LevelInfo, msg, pcs[0])
+	for _, fn := range s.opts.ContextAttrFuncs {
+		attrs = append(attrs, fn(ctx)...)
+	}
+
 	for idx, attr := range attrs {
 		if ve, ok := attr.(error); ok && ve != nil {
 			attrs[idx] = slog.String(s.opts.ErrorKey, ve.Error())
@@ -206,19 +270,41 @@ func (s *slogLogger) Info(ctx context.Context, msg string, attrs ...interface{})
 		}
 	}
 	r.Add(attrs...)
-	_ = s.handler.Handle(ctx, r)
+	_ = s.slog.Handler().Handle(ctx, r)
 }
 
-func (s *slogLogger) Debug(ctx context.Context, msg string, attrs ...interface{}) {
+func (s *slogLogger) Debug(ctx context.Context, attrs ...interface{}) {
 	if !s.V(logger.DebugLevel) {
 		return
 	}
 	var pcs [1]uintptr
 	runtime.Callers(s.opts.CallerSkipCount, pcs[:]) // skip [Callers, Infof]
-	r := slog.NewRecord(s.opts.TimeFunc(), slog.LevelDebug, msg, pcs[0])
+	r := slog.NewRecord(time.Now(), slog.LevelDebug, fmt.Sprintf("%s", attrs[0]), pcs[0])
 	for _, fn := range s.opts.ContextAttrFuncs {
 		attrs = append(attrs, fn(ctx)...)
 	}
+
+	for idx, attr := range attrs {
+		if ve, ok := attr.(error); ok && ve != nil {
+			attrs[idx] = slog.String(s.opts.ErrorKey, ve.Error())
+			break
+		}
+	}
+	r.Add(attrs[1:]...)
+	_ = s.slog.Handler().Handle(ctx, r)
+}
+
+func (s *slogLogger) Debugf(ctx context.Context, msg string, attrs ...interface{}) {
+	if !s.V(logger.DebugLevel) {
+		return
+	}
+	var pcs [1]uintptr
+	runtime.Callers(s.opts.CallerSkipCount, pcs[:]) // skip [Callers, Infof]
+	r := slog.NewRecord(time.Now(), slog.LevelDebug, msg, pcs[0])
+	for _, fn := range s.opts.ContextAttrFuncs {
+		attrs = append(attrs, fn(ctx)...)
+	}
+
 	for idx, attr := range attrs {
 		if ve, ok := attr.(error); ok && ve != nil {
 			attrs[idx] = slog.String(s.opts.ErrorKey, ve.Error())
@@ -226,39 +312,62 @@ func (s *slogLogger) Debug(ctx context.Context, msg string, attrs ...interface{}
 		}
 	}
 	r.Add(attrs...)
-	_ = s.handler.Handle(ctx, r)
+	_ = s.slog.Handler().Handle(ctx, r)
 }
 
-func (s *slogLogger) Trace(ctx context.Context, msg string, attrs ...interface{}) {
+func (s *slogLogger) Trace(ctx context.Context, attrs ...interface{}) {
 	if !s.V(logger.TraceLevel) {
 		return
 	}
 	var pcs [1]uintptr
 	runtime.Callers(s.opts.CallerSkipCount, pcs[:]) // skip [Callers, Infof]
-	r := slog.NewRecord(s.opts.TimeFunc(), slog.LevelDebug-1, msg, pcs[0])
+	r := slog.NewRecord(time.Now(), slog.LevelDebug-1, fmt.Sprintf("%s", attrs[0]), pcs[0])
 	for _, fn := range s.opts.ContextAttrFuncs {
 		attrs = append(attrs, fn(ctx)...)
 	}
+
 	for idx, attr := range attrs {
 		if ve, ok := attr.(error); ok && ve != nil {
 			attrs[idx] = slog.String(s.opts.ErrorKey, ve.Error())
 			break
 		}
 	}
-	r.Add(attrs...)
-	_ = s.handler.Handle(ctx, r)
+	r.Add(attrs[1:]...)
+	_ = s.slog.Handler().Handle(ctx, r)
 }
 
-func (s *slogLogger) Error(ctx context.Context, msg string, attrs ...interface{}) {
+func (s *slogLogger) Tracef(ctx context.Context, msg string, attrs ...interface{}) {
+	if !s.V(logger.TraceLevel) {
+		return
+	}
+	var pcs [1]uintptr
+	runtime.Callers(s.opts.CallerSkipCount, pcs[:]) // skip [Callers, Infof]
+	r := slog.NewRecord(time.Now(), slog.LevelDebug-1, msg, pcs[0])
+	for _, fn := range s.opts.ContextAttrFuncs {
+		attrs = append(attrs, fn(ctx)...)
+	}
+
+	for idx, attr := range attrs {
+		if ve, ok := attr.(error); ok && ve != nil {
+			attrs[idx] = slog.String(s.opts.ErrorKey, ve.Error())
+			break
+		}
+	}
+	r.Add(attrs[1:]...)
+	_ = s.slog.Handler().Handle(ctx, r)
+}
+
+func (s *slogLogger) Error(ctx context.Context, attrs ...interface{}) {
 	if !s.V(logger.ErrorLevel) {
 		return
 	}
 	var pcs [1]uintptr
 	runtime.Callers(s.opts.CallerSkipCount, pcs[:]) // skip [Callers, Infof]
-	r := slog.NewRecord(s.opts.TimeFunc(), slog.LevelError, msg, pcs[0])
+	r := slog.NewRecord(time.Now(), slog.LevelError, fmt.Sprintf("%s", attrs[0]), pcs[0])
 	for _, fn := range s.opts.ContextAttrFuncs {
 		attrs = append(attrs, fn(ctx)...)
 	}
+
 	for idx, attr := range attrs {
 		if ve, ok := attr.(error); ok && ve != nil {
 			attrs[idx] = slog.String(s.opts.ErrorKey, ve.Error())
@@ -270,7 +379,46 @@ func (s *slogLogger) Error(ctx context.Context, msg string, attrs ...interface{}
 		if stackSize := runtime.Stack(stackInfo, false); stackSize > 0 {
 			traceLines := reTrace.Split(string(stackInfo[:stackSize]), -1)
 			if len(traceLines) != 0 {
-				attrs = append(attrs, slog.String(s.opts.StacktraceKey, traceLines[len(traceLines)-1]))
+				attrs = append(attrs, slog.String("stacktrace", traceLines[len(traceLines)-1]))
+			}
+		}
+	}
+	r.Add(attrs[1:]...)
+	r.Attrs(func(a slog.Attr) bool {
+		if a.Key == s.opts.ErrorKey {
+			if span, ok := tracer.SpanFromContext(ctx); ok {
+				span.SetStatus(tracer.SpanStatusError, a.Value.String())
+				return false
+			}
+		}
+		return true
+	})
+	_ = s.slog.Handler().Handle(ctx, r)
+}
+
+func (s *slogLogger) Errorf(ctx context.Context, msg string, attrs ...interface{}) {
+	if !s.V(logger.ErrorLevel) {
+		return
+	}
+	var pcs [1]uintptr
+	runtime.Callers(s.opts.CallerSkipCount, pcs[:]) // skip [Callers, Infof]
+	r := slog.NewRecord(time.Now(), slog.LevelError, msg, pcs[0])
+	for _, fn := range s.opts.ContextAttrFuncs {
+		attrs = append(attrs, fn(ctx)...)
+	}
+
+	for idx, attr := range attrs {
+		if ve, ok := attr.(error); ok && ve != nil {
+			attrs[idx] = slog.String(s.opts.ErrorKey, ve.Error())
+			break
+		}
+	}
+	if s.opts.AddStacktrace {
+		stackInfo := make([]byte, 1024*1024)
+		if stackSize := runtime.Stack(stackInfo, false); stackSize > 0 {
+			traceLines := reTrace.Split(string(stackInfo[:stackSize]), -1)
+			if len(traceLines) != 0 {
+				attrs = append(attrs, slog.String("stacktrace", traceLines[len(traceLines)-1]))
 			}
 		}
 	}
@@ -284,19 +432,42 @@ func (s *slogLogger) Error(ctx context.Context, msg string, attrs ...interface{}
 		}
 		return true
 	})
-	_ = s.handler.Handle(ctx, r)
+	_ = s.slog.Handler().Handle(ctx, r)
 }
 
-func (s *slogLogger) Fatal(ctx context.Context, msg string, attrs ...interface{}) {
+func (s *slogLogger) Fatal(ctx context.Context, attrs ...interface{}) {
 	if !s.V(logger.FatalLevel) {
 		return
 	}
 	var pcs [1]uintptr
 	runtime.Callers(s.opts.CallerSkipCount, pcs[:]) // skip [Callers, Infof]
-	r := slog.NewRecord(s.opts.TimeFunc(), slog.LevelError+1, msg, pcs[0])
+	r := slog.NewRecord(time.Now(), slog.LevelError+1, fmt.Sprintf("%s", attrs[0]), pcs[0])
 	for _, fn := range s.opts.ContextAttrFuncs {
 		attrs = append(attrs, fn(ctx)...)
 	}
+
+	for idx, attr := range attrs {
+		if ve, ok := attr.(error); ok && ve != nil {
+			attrs[idx] = slog.String(s.opts.ErrorKey, ve.Error())
+			break
+		}
+	}
+	r.Add(attrs[1:]...)
+	_ = s.slog.Handler().Handle(ctx, r)
+	os.Exit(1)
+}
+
+func (s *slogLogger) Fatalf(ctx context.Context, msg string, attrs ...interface{}) {
+	if !s.V(logger.FatalLevel) {
+		return
+	}
+	var pcs [1]uintptr
+	runtime.Callers(s.opts.CallerSkipCount, pcs[:]) // skip [Callers, Infof]
+	r := slog.NewRecord(time.Now(), slog.LevelError+1, msg, pcs[0])
+	for _, fn := range s.opts.ContextAttrFuncs {
+		attrs = append(attrs, fn(ctx)...)
+	}
+
 	for idx, attr := range attrs {
 		if ve, ok := attr.(error); ok && ve != nil {
 			attrs[idx] = slog.String(s.opts.ErrorKey, ve.Error())
@@ -304,28 +475,50 @@ func (s *slogLogger) Fatal(ctx context.Context, msg string, attrs ...interface{}
 		}
 	}
 	r.Add(attrs...)
-	_ = s.handler.Handle(ctx, r)
+	_ = s.slog.Handler().Handle(ctx, r)
 	os.Exit(1)
 }
 
-func (s *slogLogger) Warn(ctx context.Context, msg string, attrs ...interface{}) {
+func (s *slogLogger) Warn(ctx context.Context, attrs ...interface{}) {
 	if !s.V(logger.WarnLevel) {
 		return
 	}
 	var pcs [1]uintptr
 	runtime.Callers(s.opts.CallerSkipCount, pcs[:]) // skip [Callers, Infof]
-	r := slog.NewRecord(s.opts.TimeFunc(), slog.LevelWarn, msg, pcs[0])
+	r := slog.NewRecord(time.Now(), slog.LevelWarn, fmt.Sprintf("%s", attrs[0]), pcs[0])
 	for _, fn := range s.opts.ContextAttrFuncs {
 		attrs = append(attrs, fn(ctx)...)
 	}
+
 	for idx, attr := range attrs {
 		if ve, ok := attr.(error); ok && ve != nil {
 			attrs[idx] = slog.String(s.opts.ErrorKey, ve.Error())
 			break
 		}
 	}
-	r.Add(attrs...)
-	_ = s.handler.Handle(ctx, r)
+	r.Add(attrs[1:]...)
+	_ = s.slog.Handler().Handle(ctx, r)
+}
+
+func (s *slogLogger) Warnf(ctx context.Context, msg string, attrs ...interface{}) {
+	if !s.V(logger.WarnLevel) {
+		return
+	}
+	var pcs [1]uintptr
+	runtime.Callers(s.opts.CallerSkipCount, pcs[:]) // skip [Callers, Infof]
+	r := slog.NewRecord(time.Now(), slog.LevelWarn, msg, pcs[0])
+	for _, fn := range s.opts.ContextAttrFuncs {
+		attrs = append(attrs, fn(ctx)...)
+	}
+
+	for idx, attr := range attrs {
+		if ve, ok := attr.(error); ok && ve != nil {
+			attrs[idx] = slog.String(s.opts.ErrorKey, ve.Error())
+			break
+		}
+	}
+	r.Add(attrs[1:]...)
+	_ = s.slog.Handler().Handle(ctx, r)
 }
 
 func (s *slogLogger) Name() string {
@@ -336,11 +529,12 @@ func (s *slogLogger) String() string {
 	return "slog"
 }
 
-func NewLogger(opts ...options.Option) logger.Logger {
-	l := &slogLogger{
+func NewLogger(opts ...logger.Option) logger.Logger {
+	s := &slogLogger{
 		opts: logger.NewOptions(opts...),
 	}
-	return l
+
+	return s
 }
 
 func loggerToSlogLevel(level logger.Level) slog.Level {

logger/slog/slog_test.go

@@ -7,20 +7,41 @@ import (
 	"log"
 	"testing"
 
-	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v3/logger"
 )
 
 func TestError(t *testing.T) {
 	ctx := context.TODO()
 	buf := bytes.NewBuffer(nil)
-	l := NewLogger(logger.WithLevel(logger.ErrorLevel), logger.WithOutput(buf), logger.WithAddStacktrace(true))
+	l := NewLogger(logger.WithLevel(logger.ErrorLevel), logger.WithOutput(buf), logger.WithStacktrace(true))
 	if err := l.Init(); err != nil {
 		t.Fatal(err)
 	}
-	l.Error(ctx, "msg", fmt.Errorf("message"))
+
+	l.Error(ctx, "message", fmt.Errorf("error message"))
 	if !bytes.Contains(buf.Bytes(), []byte(`"stacktrace":"`)) {
 		t.Fatalf("logger stacktrace not works, buf contains: %s", buf.Bytes())
 	}
+	if !bytes.Contains(buf.Bytes(), []byte(`"error":"`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestErrorf(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.ErrorLevel), logger.WithOutput(buf), logger.WithStacktrace(true))
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Errorf(ctx, "message", fmt.Errorf("error message"))
+	if !bytes.Contains(buf.Bytes(), []byte(`"stacktrace":"`)) {
+		t.Fatalf("logger stacktrace not works, buf contains: %s", buf.Bytes())
+	}
+	if !bytes.Contains(buf.Bytes(), []byte(`"error":"`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
 }
 
 func TestContext(t *testing.T) {
@@ -31,7 +52,7 @@ func TestContext(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	nl, ok := logger.FromContext(logger.NewContext(ctx, l.Attrs("key", "val")))
+	nl, ok := logger.FromContext(logger.NewContext(ctx, l.Fields("key", "val")))
 	if !ok {
 		t.Fatal("context without logger")
 	}
@@ -41,7 +62,7 @@ func TestContext(t *testing.T) {
 	}
 }
 
-func TestAttrs(t *testing.T) {
+func TestFields(t *testing.T) {
 	ctx := context.TODO()
 	buf := bytes.NewBuffer(nil)
 	l := NewLogger(logger.WithLevel(logger.TraceLevel), logger.WithOutput(buf))
@@ -49,7 +70,7 @@ func TestAttrs(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	nl := l.Attrs("key", "val")
+	nl := l.Fields("key", "val")
 
 	nl.Info(ctx, "message")
 	if !bytes.Contains(buf.Bytes(), []byte(`"key":"val"`)) {
@@ -65,7 +86,7 @@ func TestFromContextWithFields(t *testing.T) {
 	if err := l.Init(); err != nil {
 		t.Fatal(err)
 	}
-	nl := l.Attrs("key", "val")
+	nl := l.Fields("key", "val")
 
 	ctx = logger.NewContext(ctx, nl)
 
@@ -137,7 +158,7 @@ func TestLogger(t *testing.T) {
 	}
 	l.Trace(ctx, "trace_msg1")
 	l.Warn(ctx, "warn_msg1")
-	l.Attrs("error", "test").Info(ctx, "error message")
+	l.Fields("error", "test").Info(ctx, "error message")
 	l.Warn(ctx, "first second")
 
 	if !(bytes.Contains(buf.Bytes(), []byte(`"level":"trace"`)) && bytes.Contains(buf.Bytes(), []byte(`"msg":"trace_msg1"`))) {

logger/stdlogger.go

@@ -12,7 +12,7 @@ type stdLogger struct {
 
 // NewStdLogger returns new *log.Logger baked by logger.Logger implementation
 func NewStdLogger(l Logger, level Level) *log.Logger {
-	return log.New(&stdLogger{l: l.Clone(WithCallerSkipCount(l.Options().CallerSkipCount + 1)), level: level}, "" /* prefix */, 0 /* flags */)
+	return log.New(&stdLogger{l: l, level: level}, "" /* prefix */, 0 /* flags */)
 }
 
 func (sl *stdLogger) Write(p []byte) (int, error) {

logger/unwrap/unwrap.go

@@ -8,7 +8,7 @@ import (
 	"strconv"
 	"strings"
 
-	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v3/codec"
 )
 
 const sf = "0-+# "
@@ -56,9 +56,9 @@ type Wrapper struct {
 	s                fmt.State
 	pointers         map[uintptr]int
 	opts             *Options
-	takeMap          map[int]bool
 	depth            int
 	ignoreNextType   bool
+	takeMap          map[int]bool
 	protoWrapperType bool
 	sqlWrapperType   bool
 }

logger/unwrap/unwrap_test.go

@@ -5,7 +5,7 @@ import (
 	"strings"
 	"testing"
 
-	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v3/codec"
 )
 
 func TestUnwrap(t *testing.T) {

logger/wrapper/wrapper.go

@@ -0,0 +1,399 @@
+// Package wrapper provides wrapper for Logger
+package wrapper
+
+import (
+	"context"
+	"fmt"
+
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/server"
+)
+
+var (
+	// DefaultClientCallObserver called by wrapper in client Call
+	DefaultClientCallObserver = func(ctx context.Context, req client.Request, rsp interface{}, opts []client.CallOption, err error) []string {
+		labels := []string{"service", req.Service(), "endpoint", req.Endpoint()}
+		if err != nil {
+			labels = append(labels, "error", err.Error())
+		}
+		return labels
+	}
+
+	// DefaultClientStreamObserver called by wrapper in client Stream
+	DefaultClientStreamObserver = func(ctx context.Context, req client.Request, opts []client.CallOption, stream client.Stream, err error) []string {
+		labels := []string{"service", req.Service(), "endpoint", req.Endpoint()}
+		if err != nil {
+			labels = append(labels, "error", err.Error())
+		}
+		return labels
+	}
+
+	// DefaultClientPublishObserver called by wrapper in client Publish
+	DefaultClientPublishObserver = func(ctx context.Context, msg client.Message, opts []client.PublishOption, err error) []string {
+		labels := []string{"endpoint", msg.Topic()}
+		if err != nil {
+			labels = append(labels, "error", err.Error())
+		}
+		return labels
+	}
+
+	// DefaultServerHandlerObserver called by wrapper in server Handler
+	DefaultServerHandlerObserver = func(ctx context.Context, req server.Request, rsp interface{}, err error) []string {
+		labels := []string{"service", req.Service(), "endpoint", req.Endpoint()}
+		if err != nil {
+			labels = append(labels, "error", err.Error())
+		}
+		return labels
+	}
+
+	// DefaultServerSubscriberObserver called by wrapper in server Subscriber
+	DefaultServerSubscriberObserver = func(ctx context.Context, msg server.Message, err error) []string {
+		labels := []string{"endpoint", msg.Topic()}
+		if err != nil {
+			labels = append(labels, "error", err.Error())
+		}
+		return labels
+	}
+
+	// DefaultClientCallFuncObserver called by wrapper in client CallFunc
+	DefaultClientCallFuncObserver = func(ctx context.Context, addr string, req client.Request, rsp interface{}, opts client.CallOptions, err error) []string {
+		labels := []string{"service", req.Service(), "endpoint", req.Endpoint()}
+		if err != nil {
+			labels = append(labels, "error", err.Error())
+		}
+		return labels
+	}
+
+	// DefaultSkipEndpoints wrapper not called for this endpoints
+	DefaultSkipEndpoints = []string{"Meter.Metrics", "Health.Live", "Health.Ready", "Health.Version"}
+)
+
+type lWrapper struct {
+	client.Client
+	serverHandler    server.HandlerFunc
+	serverSubscriber server.SubscriberFunc
+	clientCallFunc   client.CallFunc
+	opts             Options
+}
+
+type (
+	// ClientCallObserver func signature
+	ClientCallObserver func(context.Context, client.Request, interface{}, []client.CallOption, error) []string
+	// ClientStreamObserver func signature
+	ClientStreamObserver func(context.Context, client.Request, []client.CallOption, client.Stream, error) []string
+	// ClientPublishObserver func signature
+	ClientPublishObserver func(context.Context, client.Message, []client.PublishOption, error) []string
+	// ClientCallFuncObserver func signature
+	ClientCallFuncObserver func(context.Context, string, client.Request, interface{}, client.CallOptions, error) []string
+	// ServerHandlerObserver func signature
+	ServerHandlerObserver func(context.Context, server.Request, interface{}, error) []string
+	// ServerSubscriberObserver func signature
+	ServerSubscriberObserver func(context.Context, server.Message, error) []string
+)
+
+// Options struct for wrapper
+type Options struct {
+	// Logger that used for log
+	Logger logger.Logger
+	// ServerHandlerObservers funcs
+	ServerHandlerObservers []ServerHandlerObserver
+	// ServerSubscriberObservers funcs
+	ServerSubscriberObservers []ServerSubscriberObserver
+	// ClientCallObservers funcs
+	ClientCallObservers []ClientCallObserver
+	// ClientStreamObservers funcs
+	ClientStreamObservers []ClientStreamObserver
+	// ClientPublishObservers funcs
+	ClientPublishObservers []ClientPublishObserver
+	// ClientCallFuncObservers funcs
+	ClientCallFuncObservers []ClientCallFuncObserver
+	// SkipEndpoints
+	SkipEndpoints []string
+	// Level for logger
+	Level logger.Level
+	// Enabled flag
+	Enabled bool
+}
+
+// Option func signature
+type Option func(*Options)
+
+// NewOptions creates Options from Option slice
+func NewOptions(opts ...Option) Options {
+	options := Options{
+		Logger:                    logger.DefaultLogger,
+		Level:                     logger.TraceLevel,
+		ClientCallObservers:       []ClientCallObserver{DefaultClientCallObserver},
+		ClientStreamObservers:     []ClientStreamObserver{DefaultClientStreamObserver},
+		ClientPublishObservers:    []ClientPublishObserver{DefaultClientPublishObserver},
+		ClientCallFuncObservers:   []ClientCallFuncObserver{DefaultClientCallFuncObserver},
+		ServerHandlerObservers:    []ServerHandlerObserver{DefaultServerHandlerObserver},
+		ServerSubscriberObservers: []ServerSubscriberObserver{DefaultServerSubscriberObserver},
+		SkipEndpoints:             DefaultSkipEndpoints,
+	}
+
+	for _, o := range opts {
+		o(&options)
+	}
+
+	return options
+}
+
+// WithEnabled enable/diable flag
+func WithEnabled(b bool) Option {
+	return func(o *Options) {
+		o.Enabled = b
+	}
+}
+
+// WithLevel log level
+func WithLevel(l logger.Level) Option {
+	return func(o *Options) {
+		o.Level = l
+	}
+}
+
+// WithLogger logger
+func WithLogger(l logger.Logger) Option {
+	return func(o *Options) {
+		o.Logger = l
+	}
+}
+
+// WithClientCallObservers funcs
+func WithClientCallObservers(ob ...ClientCallObserver) Option {
+	return func(o *Options) {
+		o.ClientCallObservers = ob
+	}
+}
+
+// WithClientStreamObservers funcs
+func WithClientStreamObservers(ob ...ClientStreamObserver) Option {
+	return func(o *Options) {
+		o.ClientStreamObservers = ob
+	}
+}
+
+// WithClientPublishObservers funcs
+func WithClientPublishObservers(ob ...ClientPublishObserver) Option {
+	return func(o *Options) {
+		o.ClientPublishObservers = ob
+	}
+}
+
+// WithClientCallFuncObservers funcs
+func WithClientCallFuncObservers(ob ...ClientCallFuncObserver) Option {
+	return func(o *Options) {
+		o.ClientCallFuncObservers = ob
+	}
+}
+
+// WithServerHandlerObservers funcs
+func WithServerHandlerObservers(ob ...ServerHandlerObserver) Option {
+	return func(o *Options) {
+		o.ServerHandlerObservers = ob
+	}
+}
+
+// WithServerSubscriberObservers funcs
+func WithServerSubscriberObservers(ob ...ServerSubscriberObserver) Option {
+	return func(o *Options) {
+		o.ServerSubscriberObservers = ob
+	}
+}
+
+// SkipEndpoins
+func SkipEndpoints(eps ...string) Option {
+	return func(o *Options) {
+		o.SkipEndpoints = append(o.SkipEndpoints, eps...)
+	}
+}
+
+func (l *lWrapper) Call(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
+	err := l.Client.Call(ctx, req, rsp, opts...)
+
+	endpoint := fmt.Sprintf("%s.%s", req.Service(), req.Endpoint())
+	for _, ep := range l.opts.SkipEndpoints {
+		if ep == endpoint {
+			return err
+		}
+	}
+
+	if !l.opts.Enabled {
+		return err
+	}
+
+	var labels []string
+	for _, o := range l.opts.ClientCallObservers {
+		labels = append(labels, o(ctx, req, rsp, opts, err)...)
+	}
+	l.opts.Logger.Fields(labels).Log(ctx, l.opts.Level)
+
+	return err
+}
+
+func (l *lWrapper) Stream(ctx context.Context, req client.Request, opts ...client.CallOption) (client.Stream, error) {
+	stream, err := l.Client.Stream(ctx, req, opts...)
+
+	endpoint := fmt.Sprintf("%s.%s", req.Service(), req.Endpoint())
+	for _, ep := range l.opts.SkipEndpoints {
+		if ep == endpoint {
+			return stream, err
+		}
+	}
+
+	if !l.opts.Enabled {
+		return stream, err
+	}
+
+	var labels []string
+	for _, o := range l.opts.ClientStreamObservers {
+		labels = append(labels, o(ctx, req, opts, stream, err)...)
+	}
+	l.opts.Logger.Fields(labels).Log(ctx, l.opts.Level)
+
+	return stream, err
+}
+
+func (l *lWrapper) Publish(ctx context.Context, msg client.Message, opts ...client.PublishOption) error {
+	err := l.Client.Publish(ctx, msg, opts...)
+
+	endpoint := msg.Topic()
+	for _, ep := range l.opts.SkipEndpoints {
+		if ep == endpoint {
+			return err
+		}
+	}
+
+	if !l.opts.Enabled {
+		return err
+	}
+
+	var labels []string
+	for _, o := range l.opts.ClientPublishObservers {
+		labels = append(labels, o(ctx, msg, opts, err)...)
+	}
+	l.opts.Logger.Fields(labels).Log(ctx, l.opts.Level)
+
+	return err
+}
+
+func (l *lWrapper) ServerHandler(ctx context.Context, req server.Request, rsp interface{}) error {
+	err := l.serverHandler(ctx, req, rsp)
+
+	endpoint := req.Endpoint()
+	for _, ep := range l.opts.SkipEndpoints {
+		if ep == endpoint {
+			return err
+		}
+	}
+
+	if !l.opts.Enabled {
+		return err
+	}
+
+	var labels []string
+	for _, o := range l.opts.ServerHandlerObservers {
+		labels = append(labels, o(ctx, req, rsp, err)...)
+	}
+	l.opts.Logger.Fields(labels).Log(ctx, l.opts.Level)
+
+	return err
+}
+
+func (l *lWrapper) ServerSubscriber(ctx context.Context, msg server.Message) error {
+	err := l.serverSubscriber(ctx, msg)
+
+	endpoint := msg.Topic()
+	for _, ep := range l.opts.SkipEndpoints {
+		if ep == endpoint {
+			return err
+		}
+	}
+
+	if !l.opts.Enabled {
+		return err
+	}
+
+	var labels []string
+	for _, o := range l.opts.ServerSubscriberObservers {
+		labels = append(labels, o(ctx, msg, err)...)
+	}
+	l.opts.Logger.Fields(labels).Log(ctx, l.opts.Level)
+
+	return err
+}
+
+// NewClientWrapper accepts an open options and returns a Client Wrapper
+func NewClientWrapper(opts ...Option) client.Wrapper {
+	return func(c client.Client) client.Client {
+		options := NewOptions()
+		for _, o := range opts {
+			o(&options)
+		}
+		return &lWrapper{opts: options, Client: c}
+	}
+}
+
+// NewClientCallWrapper accepts an options and returns a Call Wrapper
+func NewClientCallWrapper(opts ...Option) client.CallWrapper {
+	return func(h client.CallFunc) client.CallFunc {
+		options := NewOptions()
+		for _, o := range opts {
+			o(&options)
+		}
+
+		l := &lWrapper{opts: options, clientCallFunc: h}
+		return l.ClientCallFunc
+	}
+}
+
+func (l *lWrapper) ClientCallFunc(ctx context.Context, addr string, req client.Request, rsp interface{}, opts client.CallOptions) error {
+	err := l.clientCallFunc(ctx, addr, req, rsp, opts)
+
+	endpoint := fmt.Sprintf("%s.%s", req.Service(), req.Endpoint())
+	for _, ep := range l.opts.SkipEndpoints {
+		if ep == endpoint {
+			return err
+		}
+	}
+
+	if !l.opts.Enabled {
+		return err
+	}
+
+	var labels []string
+	for _, o := range l.opts.ClientCallFuncObservers {
+		labels = append(labels, o(ctx, addr, req, rsp, opts, err)...)
+	}
+	l.opts.Logger.Fields(labels).Log(ctx, l.opts.Level)
+
+	return err
+}
+
+// NewServerHandlerWrapper accepts an options and returns a Handler Wrapper
+func NewServerHandlerWrapper(opts ...Option) server.HandlerWrapper {
+	return func(h server.HandlerFunc) server.HandlerFunc {
+		options := NewOptions()
+		for _, o := range opts {
+			o(&options)
+		}
+
+		l := &lWrapper{opts: options, serverHandler: h}
+		return l.ServerHandler
+	}
+}
+
+// NewServerSubscriberWrapper accepts an options and returns a Subscriber Wrapper
+func NewServerSubscriberWrapper(opts ...Option) server.SubscriberWrapper {
+	return func(h server.SubscriberFunc) server.SubscriberFunc {
+		options := NewOptions()
+		for _, o := range opts {
+			o(&options)
+		}
+
+		l := &lWrapper{opts: options, serverSubscriber: h}
+		return l.ServerSubscriber
+	}
+}

metadata/context.go

@@ -17,11 +17,11 @@ func FromIncomingContext(ctx context.Context) (Metadata, bool) {
 	if ctx == nil {
 		return nil, false
 	}
-	md, ok := ctx.Value(mdIncomingKey{}).(Metadata)
-	if !ok || md == nil {
+	md, ok := ctx.Value(mdIncomingKey{}).(*rawMetadata)
+	if !ok || md.md == nil {
 		return nil, false
 	}
-	return md, ok
+	return md.md, ok
 }
 
 // FromOutgoingContext returns metadata from outgoing ctx
@@ -30,11 +30,11 @@ func FromOutgoingContext(ctx context.Context) (Metadata, bool) {
 	if ctx == nil {
 		return nil, false
 	}
-	md, ok := ctx.Value(mdOutgoingKey{}).(Metadata)
-	if !ok || md == nil {
+	md, ok := ctx.Value(mdOutgoingKey{}).(*rawMetadata)
+	if !ok || md.md == nil {
 		return nil, false
 	}
-	return md, ok
+	return md.md, ok
 }
 
 // FromContext returns metadata from the given context
@@ -43,11 +43,11 @@ func FromContext(ctx context.Context) (Metadata, bool) {
 	if ctx == nil {
 		return nil, false
 	}
-	md, ok := ctx.Value(mdKey{}).(Metadata)
-	if !ok || md == nil {
+	md, ok := ctx.Value(mdKey{}).(*rawMetadata)
+	if !ok || md.md == nil {
 		return nil, false
 	}
-	return md, ok
+	return md.md, ok
 }
 
 // NewContext creates a new context with the given metadata
@@ -55,16 +55,45 @@ func NewContext(ctx context.Context, md Metadata) context.Context {
 	if ctx == nil {
 		ctx = context.Background()
 	}
-	ctx = context.WithValue(ctx, mdKey{}, md)
+	ctx = context.WithValue(ctx, mdKey{}, &rawMetadata{md})
+	ctx = context.WithValue(ctx, mdIncomingKey{}, &rawMetadata{})
+	ctx = context.WithValue(ctx, mdOutgoingKey{}, &rawMetadata{})
 	return ctx
 }
 
+// SetOutgoingContext modify outgoing context with given metadata
+func SetOutgoingContext(ctx context.Context, md Metadata) bool {
+	if ctx == nil {
+		return false
+	}
+	if omd, ok := ctx.Value(mdOutgoingKey{}).(*rawMetadata); ok {
+		omd.md = md
+		return true
+	}
+	return false
+}
+
+// SetIncomingContext modify incoming context with given metadata
+func SetIncomingContext(ctx context.Context, md Metadata) bool {
+	if ctx == nil {
+		return false
+	}
+	if omd, ok := ctx.Value(mdIncomingKey{}).(*rawMetadata); ok {
+		omd.md = md
+		return true
+	}
+	return false
+}
+
 // NewIncomingContext creates a new context with incoming metadata attached
 func NewIncomingContext(ctx context.Context, md Metadata) context.Context {
 	if ctx == nil {
 		ctx = context.Background()
 	}
-	ctx = context.WithValue(ctx, mdIncomingKey{}, md)
+	ctx = context.WithValue(ctx, mdIncomingKey{}, &rawMetadata{md})
+	if v, ok := ctx.Value(mdOutgoingKey{}).(*rawMetadata); !ok || v == nil {
+		ctx = context.WithValue(ctx, mdOutgoingKey{}, &rawMetadata{})
+	}
 	return ctx
 }
 
@@ -73,28 +102,41 @@ func NewOutgoingContext(ctx context.Context, md Metadata) context.Context {
 	if ctx == nil {
 		ctx = context.Background()
 	}
-	ctx = context.WithValue(ctx, mdOutgoingKey{}, md)
+	ctx = context.WithValue(ctx, mdOutgoingKey{}, &rawMetadata{md})
+	if v, ok := ctx.Value(mdIncomingKey{}).(*rawMetadata); !ok || v == nil {
+		ctx = context.WithValue(ctx, mdIncomingKey{}, &rawMetadata{})
+	}
 	return ctx
 }
 
 // AppendOutgoingContext apends new md to context
 func AppendOutgoingContext(ctx context.Context, kv ...string) context.Context {
-	md := Pairs(kv...)
+	md, ok := Pairs(kv...)
+	if !ok {
+		return ctx
+	}
 	omd, ok := FromOutgoingContext(ctx)
 	if !ok {
 		return NewOutgoingContext(ctx, md)
 	}
-	nmd := Merge(omd, md, true)
-	return NewOutgoingContext(ctx, nmd)
+	for k, v := range md {
+		omd.Set(k, v)
+	}
+	return NewOutgoingContext(ctx, omd)
 }
 
 // AppendIncomingContext apends new md to context
 func AppendIncomingContext(ctx context.Context, kv ...string) context.Context {
-	md := Pairs(kv...)
+	md, ok := Pairs(kv...)
+	if !ok {
+		return ctx
+	}
 	omd, ok := FromIncomingContext(ctx)
 	if !ok {
 		return NewIncomingContext(ctx, md)
 	}
-	nmd := Merge(omd, md, true)
-	return NewIncomingContext(ctx, nmd)
+	for k, v := range md {
+		omd.Set(k, v)
+	}
+	return NewIncomingContext(ctx, omd)
 }

metadata/context_test.go

@@ -24,7 +24,7 @@ func TestNewNilContext(t *testing.T) {
 }
 
 func TestFromContext(t *testing.T) {
-	ctx := context.WithValue(context.TODO(), mdKey{}, New(0))
+	ctx := context.WithValue(context.TODO(), mdKey{}, &rawMetadata{New(0)})
 
 	c, ok := FromContext(ctx)
 	if c == nil || !ok {
@@ -42,7 +42,7 @@ func TestNewContext(t *testing.T) {
 }
 
 func TestFromIncomingContext(t *testing.T) {
-	ctx := context.WithValue(context.TODO(), mdIncomingKey{}, New(0))
+	ctx := context.WithValue(context.TODO(), mdIncomingKey{}, &rawMetadata{New(0)})
 
 	c, ok := FromIncomingContext(ctx)
 	if c == nil || !ok {
@@ -51,7 +51,7 @@ func TestFromIncomingContext(t *testing.T) {
 }
 
 func TestFromOutgoingContext(t *testing.T) {
-	ctx := context.WithValue(context.TODO(), mdOutgoingKey{}, New(0))
+	ctx := context.WithValue(context.TODO(), mdOutgoingKey{}, &rawMetadata{New(0)})
 
 	c, ok := FromOutgoingContext(ctx)
 	if c == nil || !ok {
@@ -59,6 +59,36 @@ func TestFromOutgoingContext(t *testing.T) {
 	}
 }
 
+func TestSetIncomingContext(t *testing.T) {
+	md := New(1)
+	md.Set("key", "val")
+	ctx := context.WithValue(context.TODO(), mdIncomingKey{}, &rawMetadata{})
+	if !SetIncomingContext(ctx, md) {
+		t.Fatal("SetIncomingContext not works")
+	}
+	md, ok := FromIncomingContext(ctx)
+	if md == nil || !ok {
+		t.Fatal("SetIncomingContext not works")
+	} else if v, ok := md.Get("key"); !ok || v != "val" {
+		t.Fatal("SetIncomingContext not works")
+	}
+}
+
+func TestSetOutgoingContext(t *testing.T) {
+	md := New(1)
+	md.Set("key", "val")
+	ctx := context.WithValue(context.TODO(), mdOutgoingKey{}, &rawMetadata{})
+	if !SetOutgoingContext(ctx, md) {
+		t.Fatal("SetOutgoingContext not works")
+	}
+	md, ok := FromOutgoingContext(ctx)
+	if md == nil || !ok {
+		t.Fatal("SetOutgoingContext not works")
+	} else if v, ok := md.Get("key"); !ok || v != "val" {
+		t.Fatal("SetOutgoingContext not works")
+	}
+}
+
 func TestNewIncomingContext(t *testing.T) {
 	md := New(1)
 	md.Set("key", "val")

metadata/metadata.go

@@ -1,9 +1,9 @@
 // Package metadata is a way of defining message headers
-package metadata
+package metadata // import "go.unistack.org/micro/v3/metadata"
 
 import (
 	"net/textproto"
-	"strings"
+	"sort"
 )
 
 var (
@@ -24,7 +24,47 @@ var (
 )
 
 // Metadata is our way of representing request headers internally.
-type Metadata map[string][]string
+// They're used at the RPC level and translate back and forth
+// from Transport headers.
+type Metadata map[string]string
+
+type rawMetadata struct {
+	md Metadata
+}
+
+// defaultMetadataSize used when need to init new Metadata
+var defaultMetadataSize = 2
+
+// Iterator used to iterate over metadata with order
+type Iterator struct {
+	md   Metadata
+	keys []string
+	cur  int
+	cnt  int
+}
+
+// Next advance iterator to next element
+func (iter *Iterator) Next(k, v *string) bool {
+	if iter.cur+1 > iter.cnt {
+		return false
+	}
+
+	*k = iter.keys[iter.cur]
+	*v = iter.md[*k]
+	iter.cur++
+	return true
+}
+
+// Iterator returns the itarator for metadata in sorted order
+func (md Metadata) Iterator() *Iterator {
+	iter := &Iterator{md: md, cnt: len(md)}
+	iter.keys = make([]string, 0, iter.cnt)
+	for k := range md {
+		iter.keys = append(iter.keys, k)
+	}
+	sort.Strings(iter.keys)
+	return iter
+}
 
 // Get returns value from metadata by key
 func (md Metadata) Get(key string) (string, bool) {
@@ -34,7 +74,7 @@ func (md Metadata) Get(key string) (string, bool) {
 		// slow path
 		val, ok = md[textproto.CanonicalMIMEHeaderKey(key)]
 	}
-	return strings.Join(val, ","), ok
+	return val, ok
 }
 
 // Set is used to store value in metadata
@@ -43,19 +83,10 @@ func (md Metadata) Set(kv ...string) {
 		kv = kv[:len(kv)-1]
 	}
 	for idx := 0; idx < len(kv); idx += 2 {
-		md[textproto.CanonicalMIMEHeaderKey(kv[idx])] = []string{kv[idx+1]}
+		md[textproto.CanonicalMIMEHeaderKey(kv[idx])] = kv[idx+1]
 	}
 }
 
-// Append is used to append value in metadata
-func (md Metadata) Append(k string, v ...string) {
-	if len(v) == 0 {
-		return
-	}
-	k = textproto.CanonicalMIMEHeaderKey(k)
-	md[k] = append(md[k], v...)
-}
-
 // Del is used to remove value from metadata
 func (md Metadata) Del(keys ...string) {
 	for _, key := range keys {
@@ -67,52 +98,46 @@ func (md Metadata) Del(keys ...string) {
 }
 
 // Copy makes a copy of the metadata
-func Copy(md Metadata, exclude ...string) Metadata {
-	nmd := make(Metadata, len(md))
-	for k, v := range md {
-		nmd[k] = v
+func Copy(md Metadata) Metadata {
+	nmd := New(len(md))
+	for key, val := range md {
+		nmd.Set(key, val)
 	}
-	nmd.Del(exclude...)
 	return nmd
 }
 
 // New return new sized metadata
 func New(size int) Metadata {
 	if size == 0 {
-		size = 2
+		size = defaultMetadataSize
 	}
 	return make(Metadata, size)
 }
 
 // Merge merges metadata to existing metadata, overwriting if specified
 func Merge(omd Metadata, mmd Metadata, overwrite bool) Metadata {
+	var ok bool
 	nmd := Copy(omd)
 	for key, val := range mmd {
-		nval, ok := nmd[key]
+		_, ok = nmd[key]
 		switch {
-		case ok && overwrite:
-			nmd[key] = nval
-			continue
 		case ok && !overwrite:
 			continue
-		case !ok:
-			for _, v := range val {
-				if v != "" {
-					nval = append(nval, v)
-				}
-			}
-			nmd[key] = nval
+		case val != "":
+			nmd.Set(key, val)
+		case ok && val == "":
+			nmd.Del(key)
 		}
 	}
 	return nmd
 }
 
 // Pairs from which metadata created
-func Pairs(kv ...string) Metadata {
+func Pairs(kv ...string) (Metadata, bool) {
 	if len(kv)%2 == 1 {
-		kv = kv[:len(kv)-1]
+		return nil, false
 	}
-	md := make(Metadata, len(kv)/2)
+	md := New(len(kv) / 2)
 	md.Set(kv...)
-	return md
+	return md, true
 }

metadata/metadata_test.go

@@ -33,52 +33,30 @@ func TestAppend(t *testing.T) {
 }
 
 func TestPairs(t *testing.T) {
-	md := Pairs("key1", "val1", "key2", "val2")
-
-	if _, ok := md.Get("key1"); !ok {
+	md, ok := Pairs("key1", "val1", "key2", "val2")
+	if !ok {
+		t.Fatal("odd number of kv")
+	}
+	if _, ok = md.Get("key1"); !ok {
 		t.Fatal("key1 not found")
 	}
 }
 
-func testIncomingCtx(ctx context.Context) {
-	if md, ok := FromIncomingContext(ctx); ok && md != nil {
-		md.Set("Key1", "Val1_new")
-		md.Set("Key3", "Val3")
-	}
+func testCtx(ctx context.Context) {
+	md := New(2)
+	md.Set("Key1", "Val1_new")
+	md.Set("Key3", "Val3")
+	SetOutgoingContext(ctx, md)
 }
 
-func testOutgoingCtx(ctx context.Context) {
-	if md, ok := FromOutgoingContext(ctx); ok && md != nil {
-		md.Set("Key1", "Val1_new")
-		md.Set("Key3", "Val3")
-	}
-}
-
-func TestIncoming(t *testing.T) {
+func TestPassing(t *testing.T) {
 	ctx := context.TODO()
 	md1 := New(2)
 	md1.Set("Key1", "Val1")
 	md1.Set("Key2", "Val2")
 
 	ctx = NewIncomingContext(ctx, md1)
-	testIncomingCtx(ctx)
-	md, ok := FromIncomingContext(ctx)
-	if !ok {
-		t.Fatalf("missing metadata from incoming context")
-	}
-	if v, ok := md.Get("Key1"); !ok || v != "Val1_new" {
-		t.Fatalf("invalid metadata value %#+v", md)
-	}
-}
-
-func TestOutgoing(t *testing.T) {
-	ctx := context.TODO()
-	md1 := New(2)
-	md1.Set("Key1", "Val1")
-	md1.Set("Key2", "Val2")
-
-	ctx = NewOutgoingContext(ctx, md1)
-	testOutgoingCtx(ctx)
+	testCtx(ctx)
 	md, ok := FromOutgoingContext(ctx)
 	if !ok {
 		t.Fatalf("missing metadata from outgoing context")
@@ -90,10 +68,10 @@ func TestOutgoing(t *testing.T) {
 
 func TestMerge(t *testing.T) {
 	omd := Metadata{
-		"key1": []string{"val1"},
+		"key1": "val1",
 	}
 	mmd := Metadata{
-		"key2": []string{"val2"},
+		"key2": "val2",
 	}
 
 	nmd := Merge(omd, mmd, true)
@@ -102,6 +80,21 @@ func TestMerge(t *testing.T) {
 	}
 }
 
+func TestIterator(t *testing.T) {
+	md := Metadata{
+		"1Last":   "last",
+		"2First":  "first",
+		"3Second": "second",
+	}
+
+	iter := md.Iterator()
+	var k, v string
+
+	for iter.Next(&k, &v) {
+		// fmt.Printf("k: %s, v: %s\n", k, v)
+	}
+}
+
 func TestMedataCanonicalKey(t *testing.T) {
 	md := New(1)
 	md.Set("x-request-id", "12345")
@@ -141,7 +134,10 @@ func TestMetadataSet(t *testing.T) {
 }
 
 func TestMetadataDelete(t *testing.T) {
-	md := Pairs("Foo", "bar", "Baz", "empty")
+	md := Metadata{
+		"Foo": "bar",
+		"Baz": "empty",
+	}
 
 	md.Del("Baz")
 	_, ok := md.Get("Baz")
@@ -160,19 +156,24 @@ func TestNilContext(t *testing.T) {
 }
 
 func TestMetadataCopy(t *testing.T) {
-	md := Pairs("Foo", "bar", "Bar", "baz")
+	md := Metadata{
+		"Foo": "bar",
+		"Bar": "baz",
+	}
 
 	cp := Copy(md)
 
 	for k, v := range md {
-		if cv := cp[k]; len(cv) != len(v) {
+		if cv := cp[k]; cv != v {
 			t.Fatalf("Got %s:%s for %s:%s", k, cv, k, v)
 		}
 	}
 }
 
 func TestMetadataContext(t *testing.T) {
-	md := Pairs("Foo", "bar")
+	md := Metadata{
+		"Foo": "bar",
+	}
 
 	ctx := NewContext(context.TODO(), md)
 
@@ -181,7 +182,7 @@ func TestMetadataContext(t *testing.T) {
 		t.Errorf("Unexpected error retrieving metadata, got %t", ok)
 	}
 
-	if len(emd["Foo"]) != len(md["Foo"]) {
+	if emd["Foo"] != md["Foo"] {
 		t.Errorf("Expected key: %s val: %s, got key: %s val: %s", "Foo", md["Foo"], "Foo", emd["Foo"])
 	}
 
@@ -189,14 +190,3 @@ func TestMetadataContext(t *testing.T) {
 		t.Errorf("Expected metadata length 1 got %d", i)
 	}
 }
-
-func TestCopy(t *testing.T) {
-	md := New(2)
-	md.Set("key1", "val1", "key2", "val2")
-	nmd := Copy(md, "key2")
-	if len(nmd) != 1 {
-		t.Fatal("Copy exclude not works")
-	} else if nmd["Key1"][0] != "val1" {
-		t.Fatal("Copy exclude not works")
-	}
-}

meter/context.go

@@ -22,3 +22,13 @@ func NewContext(ctx context.Context, c Meter) context.Context {
 	}
 	return context.WithValue(ctx, meterKey{}, c)
 }
+
+// SetOption returns a function to setup a context with given value
+func SetOption(k, v interface{}) Option {
+	return func(o *Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}

meter/context_test.go

@@ -40,3 +40,14 @@ func TestNewContext(t *testing.T) {
 		t.Fatal("NewContext not works")
 	}
 }
+
+func TestSetOption(t *testing.T) {
+	type key struct{}
+	o := SetOption(key{}, "test")
+	opts := &Options{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetOption not works")
+	}
+}

meter/meter.go

@@ -1,5 +1,5 @@
 // Package meter is for instrumentation
-package meter // import "go.unistack.org/micro/v4/meter"
+package meter // import "go.unistack.org/micro/v3/meter"
 
 import (
 	"io"
@@ -7,8 +7,6 @@ import (
 	"strconv"
 	"strings"
 	"time"
-
-	"go.unistack.org/micro/v4/options"
 )
 
 var (
@@ -33,9 +31,9 @@ type Meter interface {
 	// Name returns meter name
 	Name() string
 	// Init initialize meter
-	Init(opts ...options.Option) error
+	Init(opts ...Option) error
 	// Clone create meter copy with new options
-	Clone(opts ...options.Option) Meter
+	Clone(opts ...Option) Meter
 	// Counter get or create counter
 	Counter(name string, labels ...string) Counter
 	// FloatCounter get or create float counter
@@ -43,7 +41,7 @@ type Meter interface {
 	// Gauge get or create gauge
 	Gauge(name string, fn func() float64, labels ...string) Gauge
 	// Set create new meter metrics set
-	Set(opts ...options.Option) Meter
+	Set(opts ...Option) Meter
 	// Histogram get or create histogram
 	Histogram(name string, labels ...string) Histogram
 	// Summary get or create summary
@@ -51,7 +49,7 @@ type Meter interface {
 	// SummaryExt get or create summary with spcified quantiles and window time
 	SummaryExt(name string, window time.Duration, quantiles []float64, labels ...string) Summary
 	// Write writes metrics to io.Writer
-	Write(w io.Writer, opts ...options.Option) error
+	Write(w io.Writer, opts ...Option) error
 	// Options returns meter options
 	Options() Options
 	// String return meter type

meter/noop.go

@@ -3,8 +3,6 @@ package meter
 import (
 	"io"
 	"time"
-
-	"go.unistack.org/micro/v4/options"
 )
 
 // NoopMeter is an noop implementation of Meter
@@ -13,12 +11,12 @@ type noopMeter struct {
 }
 
 // NewMeter returns a configured noop reporter:
-func NewMeter(opts ...options.Option) Meter {
+func NewMeter(opts ...Option) Meter {
 	return &noopMeter{opts: NewOptions(opts...)}
 }
 
 // Clone return old meter with new options
-func (r *noopMeter) Clone(opts ...options.Option) Meter {
+func (r *noopMeter) Clone(opts ...Option) Meter {
 	options := r.opts
 	for _, o := range opts {
 		o(&options)
@@ -31,7 +29,7 @@ func (r *noopMeter) Name() string {
 }
 
 // Init initialize options
-func (r *noopMeter) Init(opts ...options.Option) error {
+func (r *noopMeter) Init(opts ...Option) error {
 	for _, o := range opts {
 		o(&r.opts)
 	}
@@ -69,7 +67,7 @@ func (r *noopMeter) Histogram(name string, labels ...string) Histogram {
 }
 
 // Set implements the Meter interface
-func (r *noopMeter) Set(opts ...options.Option) Meter {
+func (r *noopMeter) Set(opts ...Option) Meter {
 	m := &noopMeter{opts: r.opts}
 
 	for _, o := range opts {
@@ -79,7 +77,7 @@ func (r *noopMeter) Set(opts ...options.Option) Meter {
 	return m
 }
 
-func (r *noopMeter) Write(_ io.Writer, _ ...options.Option) error {
+func (r *noopMeter) Write(w io.Writer, opts ...Option) error {
 	return nil
 }
 

meter/options.go

@@ -2,13 +2,13 @@ package meter
 
 import (
 	"context"
-	"reflect"
 
-	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/options"
-	rutil "go.unistack.org/micro/v4/util/reflect"
+	"go.unistack.org/micro/v3/logger"
 )
 
+// Option powers the configuration for metrics implementations:
+type Option func(*Options)
+
 // Options for metrics implementations
 type Options struct {
 	// Logger used for logging
@@ -34,7 +34,7 @@ type Options struct {
 }
 
 // NewOptions prepares a set of options:
-func NewOptions(opt ...options.Option) Options {
+func NewOptions(opt ...Option) Options {
 	opts := Options{
 		Address:      DefaultAddress,
 		Path:         DefaultPath,
@@ -52,23 +52,37 @@ func NewOptions(opt ...options.Option) Options {
 }
 
 // LabelPrefix sets the labels prefix
-func LabelPrefix(pref string) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, pref, ".LabelPrefix")
+func LabelPrefix(pref string) Option {
+	return func(o *Options) {
+		o.LabelPrefix = pref
 	}
 }
 
 // MetricPrefix sets the metric prefix
-func MetricPrefix(pref string) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, pref, ".MetricPrefix")
+func MetricPrefix(pref string) Option {
+	return func(o *Options) {
+		o.MetricPrefix = pref
+	}
+}
+
+// Context sets the metrics context
+func Context(ctx context.Context) Option {
+	return func(o *Options) {
+		o.Context = ctx
 	}
 }
 
 // Path used to serve metrics over HTTP
-func Path(path string) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, path, ".Path")
+func Path(value string) Option {
+	return func(o *Options) {
+		o.Path = value
+	}
+}
+
+// Address is the listen address to serve metrics
+func Address(value string) Option {
+	return func(o *Options) {
+		o.Address = value
 	}
 }
 
@@ -81,34 +95,37 @@ func TimingObjectives(value map[float64]float64) Option {
 }
 */
 
+// Logger sets the logger
+func Logger(l logger.Logger) Option {
+	return func(o *Options) {
+		o.Logger = l
+	}
+}
+
 // Labels sets the meter labels
-func Labels(ls ...string) options.Option {
-	return func(src interface{}) error {
-		v, err := options.Get(src, ".Labels")
-		if err != nil {
-			return err
-		} else if rutil.IsZero(v) {
-			v = reflect.MakeSlice(reflect.TypeOf(v), 0, len(ls)).Interface()
-		}
-		cv := reflect.ValueOf(v)
-		for _, l := range ls {
-			reflect.Append(cv, reflect.ValueOf(l))
-		}
-		err = options.Set(src, cv, ".Labels")
-		return err
+func Labels(ls ...string) Option {
+	return func(o *Options) {
+		o.Labels = append(o.Labels, ls...)
+	}
+}
+
+// Name sets the name
+func Name(n string) Option {
+	return func(o *Options) {
+		o.Name = n
 	}
 }
 
 // WriteProcessMetrics enable process metrics output for write
-func WriteProcessMetrics(b bool) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, b, ".WriteProcessMetrics")
+func WriteProcessMetrics(b bool) Option {
+	return func(o *Options) {
+		o.WriteProcessMetrics = b
 	}
 }
 
 // WriteFDMetrics enable fd metrics output for write
-func WriteFDMetrics(b bool) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, b, ".WriteFDMetrics")
+func WriteFDMetrics(b bool) Option {
+	return func(o *Options) {
+		o.WriteFDMetrics = b
 	}
 }

meter/wrapper/wrapper.go

@@ -1,18 +1,49 @@
-package wrapper
+package wrapper // import "go.unistack.org/micro/v3/meter/wrapper"
 
 import (
 	"context"
 	"fmt"
 	"time"
 
-	"go.unistack.org/micro/v4/client"
-	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v4/semconv"
-	"go.unistack.org/micro/v4/server"
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/server"
 )
 
 var (
+	// ClientRequestDurationSeconds specifies meter metric name
+	ClientRequestDurationSeconds = "client_request_duration_seconds"
+	// ClientRequestLatencyMicroseconds specifies meter metric name
+	ClientRequestLatencyMicroseconds = "client_request_latency_microseconds"
+	// ClientRequestTotal specifies meter metric name
+	ClientRequestTotal = "client_request_total"
+	// ClientRequestInflight specifies meter metric name
+	ClientRequestInflight = "client_request_inflight"
+	// ServerRequestDurationSeconds specifies meter metric name
+	ServerRequestDurationSeconds = "server_request_duration_seconds"
+	// ServerRequestLatencyMicroseconds specifies meter metric name
+	ServerRequestLatencyMicroseconds = "server_request_latency_microseconds"
+	// ServerRequestTotal specifies meter metric name
+	ServerRequestTotal = "server_request_total"
+	// ServerRequestInflight specifies meter metric name
+	ServerRequestInflight = "server_request_inflight"
+	// PublishMessageDurationSeconds specifies meter metric name
+	PublishMessageDurationSeconds = "publish_message_duration_seconds"
+	// PublishMessageLatencyMicroseconds specifies meter metric name
+	PublishMessageLatencyMicroseconds = "publish_message_latency_microseconds"
+	// PublishMessageTotal specifies meter metric name
+	PublishMessageTotal = "publish_message_total"
+	// PublishMessageInflight specifies meter metric name
+	PublishMessageInflight = "publish_message_inflight"
+	// SubscribeMessageDurationSeconds specifies meter metric name
+	SubscribeMessageDurationSeconds = "subscribe_message_duration_seconds"
+	// SubscribeMessageLatencyMicroseconds specifies meter metric name
+	SubscribeMessageLatencyMicroseconds = "subscribe_message_latency_microseconds"
+	// SubscribeMessageTotal specifies meter metric name
+	SubscribeMessageTotal = "subscribe_message_total"
+	// SubscribeMessageInflight specifies meter metric name
+	SubscribeMessageInflight = "subscribe_message_inflight"
+
 	labelSuccess  = "success"
 	labelFailure  = "failure"
 	labelStatus   = "status"
@@ -25,7 +56,7 @@ var (
 // Options struct
 type Options struct {
 	Meter         meter.Meter
-	lopts         []options.Option
+	lopts         []meter.Option
 	SkipEndpoints []string
 }
 
@@ -36,7 +67,7 @@ type Option func(*Options)
 func NewOptions(opts ...Option) Options {
 	options := Options{
 		Meter:         meter.DefaultMeter,
-		lopts:         make([]options.Option, 0, 5),
+		lopts:         make([]meter.Option, 0, 5),
 		SkipEndpoints: DefaultSkipEndpoints,
 	}
 	for _, o := range opts {
@@ -119,26 +150,26 @@ func (w *wrapper) CallFunc(ctx context.Context, addr string, req client.Request,
 	labels := make([]string, 0, 4)
 	labels = append(labels, labelEndpoint, endpoint)
 
-	w.opts.Meter.Counter(semconv.ClientRequestInflight, labels...).Inc()
+	w.opts.Meter.Counter(ClientRequestInflight, labels...).Inc()
 	ts := time.Now()
 	err := w.callFunc(ctx, addr, req, rsp, opts)
 	te := time.Since(ts)
-	w.opts.Meter.Counter(semconv.ClientRequestInflight, labels...).Dec()
+	w.opts.Meter.Counter(ClientRequestInflight, labels...).Dec()
 
-	w.opts.Meter.Summary(semconv.ClientRequestLatencyMicroseconds, labels...).Update(te.Seconds())
-	w.opts.Meter.Histogram(semconv.ClientRequestDurationSeconds, labels...).Update(te.Seconds())
+	w.opts.Meter.Summary(ClientRequestLatencyMicroseconds, labels...).Update(te.Seconds())
+	w.opts.Meter.Histogram(ClientRequestDurationSeconds, labels...).Update(te.Seconds())
 
 	if err == nil {
 		labels = append(labels, labelStatus, labelSuccess)
 	} else {
 		labels = append(labels, labelStatus, labelFailure)
 	}
-	w.opts.Meter.Counter(semconv.ClientRequestTotal, labels...).Inc()
+	w.opts.Meter.Counter(ClientRequestTotal, labels...).Inc()
 
 	return err
 }
 
-func (w *wrapper) Call(ctx context.Context, req client.Request, rsp interface{}, opts ...options.Option) error {
+func (w *wrapper) Call(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
 	endpoint := fmt.Sprintf("%s.%s", req.Service(), req.Endpoint())
 	for _, ep := range w.opts.SkipEndpoints {
 		if ep == endpoint {
@@ -149,26 +180,26 @@ func (w *wrapper) Call(ctx context.Context, req client.Request, rsp interface{},
 	labels := make([]string, 0, 4)
 	labels = append(labels, labelEndpoint, endpoint)
 
-	w.opts.Meter.Counter(semconv.ClientRequestInflight, labels...).Inc()
+	w.opts.Meter.Counter(ClientRequestInflight, labels...).Inc()
 	ts := time.Now()
 	err := w.Client.Call(ctx, req, rsp, opts...)
 	te := time.Since(ts)
-	w.opts.Meter.Counter(semconv.ClientRequestInflight, labels...).Dec()
+	w.opts.Meter.Counter(ClientRequestInflight, labels...).Dec()
 
-	w.opts.Meter.Summary(semconv.ClientRequestLatencyMicroseconds, labels...).Update(te.Seconds())
-	w.opts.Meter.Histogram(semconv.ClientRequestDurationSeconds, labels...).Update(te.Seconds())
+	w.opts.Meter.Summary(ClientRequestLatencyMicroseconds, labels...).Update(te.Seconds())
+	w.opts.Meter.Histogram(ClientRequestDurationSeconds, labels...).Update(te.Seconds())
 
 	if err == nil {
 		labels = append(labels, labelStatus, labelSuccess)
 	} else {
 		labels = append(labels, labelStatus, labelFailure)
 	}
-	w.opts.Meter.Counter(semconv.ClientRequestTotal, labels...).Inc()
+	w.opts.Meter.Counter(ClientRequestTotal, labels...).Inc()
 
 	return err
 }
 
-func (w *wrapper) Stream(ctx context.Context, req client.Request, opts ...options.Option) (client.Stream, error) {
+func (w *wrapper) Stream(ctx context.Context, req client.Request, opts ...client.CallOption) (client.Stream, error) {
 	endpoint := fmt.Sprintf("%s.%s", req.Service(), req.Endpoint())
 	for _, ep := range w.opts.SkipEndpoints {
 		if ep == endpoint {
@@ -179,25 +210,59 @@ func (w *wrapper) Stream(ctx context.Context, req client.Request, opts ...option
 	labels := make([]string, 0, 4)
 	labels = append(labels, labelEndpoint, endpoint)
 
-	w.opts.Meter.Counter(semconv.ClientRequestInflight, labels...).Inc()
+	w.opts.Meter.Counter(ClientRequestInflight, labels...).Inc()
 	ts := time.Now()
 	stream, err := w.Client.Stream(ctx, req, opts...)
 	te := time.Since(ts)
-	w.opts.Meter.Counter(semconv.ClientRequestInflight, labels...).Dec()
+	w.opts.Meter.Counter(ClientRequestInflight, labels...).Dec()
 
-	w.opts.Meter.Summary(semconv.ClientRequestLatencyMicroseconds, labels...).Update(te.Seconds())
-	w.opts.Meter.Histogram(semconv.ClientRequestDurationSeconds, labels...).Update(te.Seconds())
+	w.opts.Meter.Summary(ClientRequestLatencyMicroseconds, labels...).Update(te.Seconds())
+	w.opts.Meter.Histogram(ClientRequestDurationSeconds, labels...).Update(te.Seconds())
 
 	if err == nil {
 		labels = append(labels, labelStatus, labelSuccess)
 	} else {
 		labels = append(labels, labelStatus, labelFailure)
 	}
-	w.opts.Meter.Counter(semconv.ClientRequestTotal, labels...).Inc()
+	w.opts.Meter.Counter(ClientRequestTotal, labels...).Inc()
 
 	return stream, err
 }
 
+func (w *wrapper) Publish(ctx context.Context, p client.Message, opts ...client.PublishOption) error {
+	endpoint := p.Topic()
+
+	labels := make([]string, 0, 4)
+	labels = append(labels, labelEndpoint, endpoint)
+
+	w.opts.Meter.Counter(PublishMessageInflight, labels...).Inc()
+	ts := time.Now()
+	err := w.Client.Publish(ctx, p, opts...)
+	te := time.Since(ts)
+	w.opts.Meter.Counter(PublishMessageInflight, labels...).Dec()
+
+	w.opts.Meter.Summary(PublishMessageLatencyMicroseconds, labels...).Update(te.Seconds())
+	w.opts.Meter.Histogram(PublishMessageDurationSeconds, labels...).Update(te.Seconds())
+
+	if err == nil {
+		labels = append(labels, labelStatus, labelSuccess)
+	} else {
+		labels = append(labels, labelStatus, labelFailure)
+	}
+	w.opts.Meter.Counter(PublishMessageTotal, labels...).Inc()
+
+	return err
+}
+
+// NewHandlerWrapper create new server handler wrapper
+// deprecated
+func NewHandlerWrapper(opts ...Option) server.HandlerWrapper {
+	handler := &wrapper{
+		opts: NewOptions(opts...),
+	}
+	return handler.HandlerFunc
+}
+
 // NewServerHandlerWrapper create new server handler wrapper
 func NewServerHandlerWrapper(opts ...Option) server.HandlerWrapper {
 	handler := &wrapper{
@@ -218,21 +283,64 @@ func (w *wrapper) HandlerFunc(fn server.HandlerFunc) server.HandlerFunc {
 		labels := make([]string, 0, 4)
 		labels = append(labels, labelEndpoint, endpoint)
 
-		w.opts.Meter.Counter(semconv.ServerRequestInflight, labels...).Inc()
+		w.opts.Meter.Counter(ServerRequestInflight, labels...).Inc()
 		ts := time.Now()
 		err := fn(ctx, req, rsp)
 		te := time.Since(ts)
-		w.opts.Meter.Counter(semconv.ServerRequestInflight, labels...).Dec()
+		w.opts.Meter.Counter(ServerRequestInflight, labels...).Dec()
 
-		w.opts.Meter.Summary(semconv.ServerRequestLatencyMicroseconds, labels...).Update(te.Seconds())
-		w.opts.Meter.Histogram(semconv.ServerRequestDurationSeconds, labels...).Update(te.Seconds())
+		w.opts.Meter.Summary(ServerRequestLatencyMicroseconds, labels...).Update(te.Seconds())
+		w.opts.Meter.Histogram(ServerRequestDurationSeconds, labels...).Update(te.Seconds())
 
 		if err == nil {
 			labels = append(labels, labelStatus, labelSuccess)
 		} else {
 			labels = append(labels, labelStatus, labelFailure)
 		}
-		w.opts.Meter.Counter(semconv.ServerRequestTotal, labels...).Inc()
+		w.opts.Meter.Counter(ServerRequestTotal, labels...).Inc()
+
+		return err
+	}
+}
+
+// NewSubscriberWrapper create server subscribe wrapper
+// deprecated
+func NewSubscriberWrapper(opts ...Option) server.SubscriberWrapper {
+	handler := &wrapper{
+		opts: NewOptions(opts...),
+	}
+	return handler.SubscriberFunc
+}
+
+func NewServerSubscriberWrapper(opts ...Option) server.SubscriberWrapper {
+	handler := &wrapper{
+		opts: NewOptions(opts...),
+	}
+	return handler.SubscriberFunc
+}
+
+func (w *wrapper) SubscriberFunc(fn server.SubscriberFunc) server.SubscriberFunc {
+	return func(ctx context.Context, msg server.Message) error {
+		endpoint := msg.Topic()
+
+		labels := make([]string, 0, 4)
+		labels = append(labels, labelEndpoint, endpoint)
+
+		w.opts.Meter.Counter(SubscribeMessageInflight, labels...).Inc()
+		ts := time.Now()
+		err := fn(ctx, msg)
+		te := time.Since(ts)
+		w.opts.Meter.Counter(SubscribeMessageInflight, labels...).Dec()
+
+		w.opts.Meter.Summary(SubscribeMessageLatencyMicroseconds, labels...).Update(te.Seconds())
+		w.opts.Meter.Histogram(SubscribeMessageDurationSeconds, labels...).Update(te.Seconds())
+
+		if err == nil {
+			labels = append(labels, labelStatus, labelSuccess)
+		} else {
+			labels = append(labels, labelStatus, labelFailure)
+		}
+		w.opts.Meter.Counter(SubscribeMessageTotal, labels...).Inc()
 
 		return err
 	}

micro.go

@@ -3,21 +3,21 @@ package micro
 import (
 	"reflect"
 
-	"go.unistack.org/micro/v4/broker"
-	"go.unistack.org/micro/v4/client"
-	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v4/flow"
-	"go.unistack.org/micro/v4/fsm"
-	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v4/register"
-	"go.unistack.org/micro/v4/resolver"
-	"go.unistack.org/micro/v4/router"
-	"go.unistack.org/micro/v4/selector"
-	"go.unistack.org/micro/v4/server"
-	"go.unistack.org/micro/v4/store"
-	"go.unistack.org/micro/v4/sync"
-	"go.unistack.org/micro/v4/tracer"
+	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/flow"
+	"go.unistack.org/micro/v3/fsm"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v3/resolver"
+	"go.unistack.org/micro/v3/router"
+	"go.unistack.org/micro/v3/selector"
+	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v3/store"
+	"go.unistack.org/micro/v3/sync"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 func As(b any, target any) bool {
@@ -65,8 +65,6 @@ func As(b any, target any) bool {
 			break
 		case targetType.Implements(routerType):
 			break
-		case targetType.Implements(tracerType):
-			break
 		default:
 			return false
 		}
@@ -78,21 +76,19 @@ func As(b any, target any) bool {
 	return false
 }
 
-var (
-	brokerType   = reflect.TypeOf((*broker.Broker)(nil)).Elem()
-	loggerType   = reflect.TypeOf((*logger.Logger)(nil)).Elem()
-	clientType   = reflect.TypeOf((*client.Client)(nil)).Elem()
-	serverType   = reflect.TypeOf((*server.Server)(nil)).Elem()
-	codecType    = reflect.TypeOf((*codec.Codec)(nil)).Elem()
-	flowType     = reflect.TypeOf((*flow.Flow)(nil)).Elem()
-	fsmType      = reflect.TypeOf((*fsm.FSM)(nil)).Elem()
-	meterType    = reflect.TypeOf((*meter.Meter)(nil)).Elem()
-	registerType = reflect.TypeOf((*register.Register)(nil)).Elem()
-	resolverType = reflect.TypeOf((*resolver.Resolver)(nil)).Elem()
-	routerType   = reflect.TypeOf((*router.Router)(nil)).Elem()
-	selectorType = reflect.TypeOf((*selector.Selector)(nil)).Elem()
-	storeType    = reflect.TypeOf((*store.Store)(nil)).Elem()
-	syncType     = reflect.TypeOf((*sync.Sync)(nil)).Elem()
-	tracerType   = reflect.TypeOf((*tracer.Tracer)(nil)).Elem()
-	serviceType  = reflect.TypeOf((*Service)(nil)).Elem()
-)
+var brokerType = reflect.TypeOf((*broker.Broker)(nil)).Elem()
+var loggerType = reflect.TypeOf((*logger.Logger)(nil)).Elem()
+var clientType = reflect.TypeOf((*client.Client)(nil)).Elem()
+var serverType = reflect.TypeOf((*server.Server)(nil)).Elem()
+var codecType = reflect.TypeOf((*codec.Codec)(nil)).Elem()
+var flowType = reflect.TypeOf((*flow.Flow)(nil)).Elem()
+var fsmType = reflect.TypeOf((*fsm.FSM)(nil)).Elem()
+var meterType = reflect.TypeOf((*meter.Meter)(nil)).Elem()
+var registerType = reflect.TypeOf((*register.Register)(nil)).Elem()
+var resolverType = reflect.TypeOf((*resolver.Resolver)(nil)).Elem()
+var routerType = reflect.TypeOf((*router.Router)(nil)).Elem()
+var selectorType = reflect.TypeOf((*selector.Selector)(nil)).Elem()
+var storeType = reflect.TypeOf((*store.Store)(nil)).Elem()
+var syncType = reflect.TypeOf((*sync.Sync)(nil)).Elem()
+var tracerType = reflect.TypeOf((*tracer.Tracer)(nil)).Elem()
+var serviceType = reflect.TypeOf((*Service)(nil)).Elem()

micro_test.go

@@ -6,9 +6,8 @@ import (
 	"reflect"
 	"testing"
 
-	"go.unistack.org/micro/v4/broker"
-	"go.unistack.org/micro/v4/fsm"
-	"go.unistack.org/micro/v4/options"
+	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v3/fsm"
 )
 
 func TestAs(t *testing.T) {
@@ -65,8 +64,9 @@ type bro struct {
 	name string
 }
 
-func (p *bro) Name() string                      { return p.name }
-func (p *bro) Init(opts ...options.Option) error { return nil }
+func (p *bro) Name() string { return p.name }
+
+func (p *bro) Init(opts ...broker.Option) error { return nil }
 
 // Options returns broker options
 func (p *bro) Options() broker.Options { return broker.Options{} }
@@ -81,10 +81,22 @@ func (p *bro) Connect(ctx context.Context) error { return nil }
 func (p *bro) Disconnect(ctx context.Context) error { return nil }
 
 // Publish message, msg can be single broker.Message or []broker.Message
-func (p *bro) Publish(ctx context.Context, msg interface{}, opts ...options.Option) error { return nil }
+func (p *bro) Publish(ctx context.Context, topic string, msg *broker.Message, opts ...broker.PublishOption) error {
+	return nil
+}
+
+// BatchPublish messages to broker with multiple topics
+func (p *bro) BatchPublish(ctx context.Context, msgs []*broker.Message, opts ...broker.PublishOption) error {
+	return nil
+}
+
+// BatchSubscribe subscribes to topic messages via handler
+func (p *bro) BatchSubscribe(ctx context.Context, topic string, h broker.BatchHandler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
+	return nil, nil
+}
 
 // Subscribe subscribes to topic message via handler
-func (p *bro) Subscribe(ctx context.Context, topic string, handler interface{}, opts ...options.Option) (broker.Subscriber, error) {
+func (p *bro) Subscribe(ctx context.Context, topic string, handler broker.Handler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
 	return nil, nil
 }
 

mtls/mtls.go

@@ -1,4 +1,4 @@
-package mtls // import "go.unistack.org/micro/v4/mtls"
+package mtls // import "go.unistack.org/micro/v3/mtls"
 
 import (
 	"bytes"

network/network.go

@@ -0,0 +1,55 @@
+// Package network is for creating internetworks
+package network // import "go.unistack.org/micro/v3/network"
+
+import (
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/server"
+)
+
+// Error is network node errors
+type Error interface {
+	// Count is current count of errors
+	Count() int
+	// Msg is last error message
+	Msg() string
+}
+
+// Status is node status
+type Status interface {
+	// Error reports error status
+	Error() Error
+}
+
+// Node is network node
+type Node interface {
+	// Id is node id
+	Id() string
+	// Address is node bind address
+	Address() string
+	// Peers returns node peers
+	Peers() []Node
+	// Network is the network node is in
+	Network() Network
+	// Status returns node status
+	Status() Status
+}
+
+// Network is micro network
+type Network interface {
+	// Node is network node
+	Node
+	// Initialise options
+	Init(...Option) error
+	// Options returns the network options
+	Options() Options
+	// Name of the network
+	Name() string
+	// Connect starts the resolver and tunnel server
+	Connect() error
+	// Close stops the tunnel and resolving
+	Close() error
+	// Client is micro client
+	Client() client.Client
+	// Server is micro server
+	Server() server.Server
+}

network/options.go

@@ -0,0 +1,135 @@
+package network
+
+import (
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/network/tunnel"
+	"go.unistack.org/micro/v3/proxy"
+	"go.unistack.org/micro/v3/router"
+	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v3/util/id"
+)
+
+// Option func
+type Option func(*Options)
+
+// Options configure network
+type Options struct {
+	// Router used for routing
+	Router router.Router
+	// Proxy holds the proxy
+	Proxy proxy.Proxy
+	// Logger used for logging
+	Logger logger.Logger
+	// Meter used for metrics
+	Meter meter.Meter
+	// Tracer used for tracing
+	Tracer tracer.Tracer
+	// Tunnel used for transfer data
+	Tunnel tunnel.Tunnel
+	// ID of the node
+	ID string
+	// Name of the network
+	Name string
+	// Address to bind to
+	Address string
+	// Advertise sets the address to advertise
+	Advertise string
+	// Nodes is a list of nodes to connect to
+	Nodes []string
+}
+
+// ID sets the id of the network node
+func ID(id string) Option {
+	return func(o *Options) {
+		o.ID = id
+	}
+}
+
+// Name sets the network name
+func Name(n string) Option {
+	return func(o *Options) {
+		o.Name = n
+	}
+}
+
+// Address sets the network address
+func Address(a string) Option {
+	return func(o *Options) {
+		o.Address = a
+	}
+}
+
+// Advertise sets the address to advertise
+func Advertise(a string) Option {
+	return func(o *Options) {
+		o.Advertise = a
+	}
+}
+
+// Nodes is a list of nodes to connect to
+func Nodes(n ...string) Option {
+	return func(o *Options) {
+		o.Nodes = n
+	}
+}
+
+// Tunnel sets the network tunnel
+func Tunnel(t tunnel.Tunnel) Option {
+	return func(o *Options) {
+		o.Tunnel = t
+	}
+}
+
+// Router sets the network router
+func Router(r router.Router) Option {
+	return func(o *Options) {
+		o.Router = r
+	}
+}
+
+// Proxy sets the network proxy
+func Proxy(p proxy.Proxy) Option {
+	return func(o *Options) {
+		o.Proxy = p
+	}
+}
+
+// Logger sets the network logger
+func Logger(l logger.Logger) Option {
+	return func(o *Options) {
+		o.Logger = l
+	}
+}
+
+// Meter sets the meter
+func Meter(m meter.Meter) Option {
+	return func(o *Options) {
+		o.Meter = m
+	}
+}
+
+// Tracer to be used for tracing
+func Tracer(t tracer.Tracer) Option {
+	return func(o *Options) {
+		o.Tracer = t
+	}
+}
+
+// NewOptions returns network default options
+func NewOptions(opts ...Option) Options {
+	options := Options{
+		ID:      id.Must(),
+		Name:    "go.micro",
+		Address: ":0",
+		Logger:  logger.DefaultLogger,
+		Meter:   meter.DefaultMeter,
+		Tracer:  tracer.DefaultTracer,
+	}
+
+	for _, o := range opts {
+		o(&options)
+	}
+
+	return options
+}

network/transport/context.go

@@ -0,0 +1,34 @@
+package transport
+
+import (
+	"context"
+)
+
+type transportKey struct{}
+
+// FromContext get transport from context
+func FromContext(ctx context.Context) (Transport, bool) {
+	if ctx == nil {
+		return nil, false
+	}
+	c, ok := ctx.Value(transportKey{}).(Transport)
+	return c, ok
+}
+
+// NewContext put transport in context
+func NewContext(ctx context.Context, c Transport) context.Context {
+	if ctx == nil {
+		ctx = context.Background()
+	}
+	return context.WithValue(ctx, transportKey{}, c)
+}
+
+// SetOption returns a function to setup a context with given value
+func SetOption(k, v interface{}) Option {
+	return func(o *Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}

network/transport/memory.go

@@ -0,0 +1,258 @@
+package transport
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net"
+	"sync"
+	"time"
+
+	maddr "go.unistack.org/micro/v3/util/addr"
+	mnet "go.unistack.org/micro/v3/util/net"
+	"go.unistack.org/micro/v3/util/rand"
+)
+
+type memorySocket struct {
+	ctx     context.Context
+	recv    chan *Message
+	exit    chan bool
+	lexit   chan bool
+	send    chan *Message
+	local   string
+	remote  string
+	timeout time.Duration
+	sync.RWMutex
+}
+
+type memoryClient struct {
+	*memorySocket
+	opts DialOptions
+}
+
+type memoryListener struct {
+	lopts ListenOptions
+	ctx   context.Context
+	exit  chan bool
+	conn  chan *memorySocket
+	addr  string
+	topts Options
+	sync.RWMutex
+}
+
+type memoryTransport struct {
+	listeners map[string]*memoryListener
+	opts      Options
+	sync.RWMutex
+}
+
+func (ms *memorySocket) Recv(m *Message) error {
+	ms.RLock()
+	defer ms.RUnlock()
+
+	ctx := ms.ctx
+	if ms.timeout > 0 {
+		var cancel context.CancelFunc
+		ctx, cancel = context.WithTimeout(ms.ctx, ms.timeout)
+		defer cancel()
+	}
+
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-ms.exit:
+		return errors.New("connection closed")
+	case <-ms.lexit:
+		return errors.New("server connection closed")
+	case cm := <-ms.recv:
+		*m = *cm
+	}
+	return nil
+}
+
+func (ms *memorySocket) Local() string {
+	return ms.local
+}
+
+func (ms *memorySocket) Remote() string {
+	return ms.remote
+}
+
+func (ms *memorySocket) Send(m *Message) error {
+	ms.RLock()
+	defer ms.RUnlock()
+
+	ctx := ms.ctx
+	if ms.timeout > 0 {
+		var cancel context.CancelFunc
+		ctx, cancel = context.WithTimeout(ms.ctx, ms.timeout)
+		defer cancel()
+	}
+
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-ms.exit:
+		return errors.New("connection closed")
+	case <-ms.lexit:
+		return errors.New("server connection closed")
+	case ms.send <- m:
+	}
+	return nil
+}
+
+func (ms *memorySocket) Close() error {
+	ms.Lock()
+	defer ms.Unlock()
+	select {
+	case <-ms.exit:
+		return nil
+	default:
+		close(ms.exit)
+	}
+	return nil
+}
+
+func (m *memoryListener) Addr() string {
+	return m.addr
+}
+
+func (m *memoryListener) Close() error {
+	m.Lock()
+	defer m.Unlock()
+	select {
+	case <-m.exit:
+		return nil
+	default:
+		close(m.exit)
+	}
+	return nil
+}
+
+func (m *memoryListener) Accept(fn func(Socket)) error {
+	for {
+		select {
+		case <-m.exit:
+			return nil
+		case c := <-m.conn:
+			go fn(&memorySocket{
+				lexit:   c.lexit,
+				exit:    c.exit,
+				send:    c.recv,
+				recv:    c.send,
+				local:   c.Remote(),
+				remote:  c.Local(),
+				timeout: m.topts.Timeout,
+				ctx:     m.topts.Context,
+			})
+		}
+	}
+}
+
+func (m *memoryTransport) Dial(ctx context.Context, addr string, opts ...DialOption) (Client, error) {
+	m.RLock()
+	defer m.RUnlock()
+
+	listener, ok := m.listeners[addr]
+	if !ok {
+		return nil, errors.New("could not dial " + addr)
+	}
+
+	options := NewDialOptions(opts...)
+
+	client := &memoryClient{
+		&memorySocket{
+			send:    make(chan *Message),
+			recv:    make(chan *Message),
+			exit:    make(chan bool),
+			lexit:   listener.exit,
+			local:   addr,
+			remote:  addr,
+			timeout: m.opts.Timeout,
+			ctx:     m.opts.Context,
+		},
+		options,
+	}
+
+	// pseudo connect
+	select {
+	case <-listener.exit:
+		return nil, errors.New("connection error")
+	case listener.conn <- client.memorySocket:
+	}
+
+	return client, nil
+}
+
+func (m *memoryTransport) Listen(ctx context.Context, addr string, opts ...ListenOption) (Listener, error) {
+	m.Lock()
+	defer m.Unlock()
+
+	options := NewListenOptions(opts...)
+
+	host, port, err := net.SplitHostPort(addr)
+	if err != nil {
+		return nil, err
+	}
+
+	addr, err = maddr.Extract(host)
+	if err != nil {
+		return nil, err
+	}
+
+	// if zero port then randomly assign one
+	if len(port) > 0 && port == "0" {
+		var rng rand.Rand
+		i := rng.Intn(20000)
+		port = fmt.Sprintf("%d", 10000+i)
+	}
+
+	// set addr with port
+	addr = mnet.HostPort(addr, port)
+
+	if _, ok := m.listeners[addr]; ok {
+		return nil, errors.New("already listening on " + addr)
+	}
+
+	listener := &memoryListener{
+		lopts: options,
+		topts: m.opts,
+		addr:  addr,
+		conn:  make(chan *memorySocket),
+		exit:  make(chan bool),
+		ctx:   m.opts.Context,
+	}
+
+	m.listeners[addr] = listener
+
+	return listener, nil
+}
+
+func (m *memoryTransport) Init(opts ...Option) error {
+	for _, o := range opts {
+		o(&m.opts)
+	}
+	return nil
+}
+
+func (m *memoryTransport) Options() Options {
+	return m.opts
+}
+
+func (m *memoryTransport) String() string {
+	return "memory"
+}
+
+func (m *memoryTransport) Name() string {
+	return m.opts.Name
+}
+
+// NewTransport returns new memory transport with options
+func NewTransport(opts ...Option) Transport {
+	options := NewOptions(opts...)
+
+	return &memoryTransport{
+		opts:      options,
+		listeners: make(map[string]*memoryListener),
+	}
+}

network/transport/memory_test.go

@@ -0,0 +1,100 @@
+package transport
+
+import (
+	"context"
+	"os"
+	"testing"
+)
+
+func TestMemoryTransport(t *testing.T) {
+	tr := NewTransport()
+	ctx := context.Background()
+	// bind / listen
+	l, err := tr.Listen(ctx, "127.0.0.1:8080")
+	if err != nil {
+		t.Fatalf("Unexpected error listening %v", err)
+	}
+	defer l.Close()
+
+	cherr := make(chan error, 1)
+	// accept
+	go func() {
+		if nerr := l.Accept(func(sock Socket) {
+			for {
+				var m Message
+				if rerr := sock.Recv(&m); rerr != nil {
+					cherr <- rerr
+					return
+				}
+				if len(os.Getenv("INTEGRATION_TESTS")) == 0 {
+					t.Logf("Server Received %s", string(m.Body))
+				}
+				if cerr := sock.Send(&Message{
+					Body: []byte(`pong`),
+				}); cerr != nil {
+					cherr <- cerr
+					return
+				}
+			}
+		}); nerr != nil {
+			cherr <- err
+		}
+	}()
+
+	// dial
+	c, err := tr.Dial(ctx, "127.0.0.1:8080")
+	if err != nil {
+		t.Fatalf("Unexpected error dialing %v", err)
+	}
+	defer c.Close()
+
+	select {
+	case err := <-cherr:
+		t.Fatal(err)
+	default:
+		// send <=> receive
+		for i := 0; i < 3; i++ {
+			if err := c.Send(&Message{
+				Body: []byte(`ping`),
+			}); err != nil {
+				return
+			}
+			var m Message
+			if err := c.Recv(&m); err != nil {
+				return
+			}
+			if len(os.Getenv("INTEGRATION_TESTS")) == 0 {
+				t.Logf("Client Received %s", string(m.Body))
+			}
+		}
+	}
+}
+
+func TestListener(t *testing.T) {
+	tr := NewTransport()
+	ctx := context.Background()
+	// bind / listen on random port
+	l, err := tr.Listen(ctx, ":0")
+	if err != nil {
+		t.Fatalf("Unexpected error listening %v", err)
+	}
+	defer l.Close()
+
+	// try again
+	l2, err := tr.Listen(ctx, ":0")
+	if err != nil {
+		t.Fatalf("Unexpected error listening %v", err)
+	}
+	defer l2.Close()
+
+	// now make sure it still fails
+	l3, err := tr.Listen(ctx, ":8080")
+	if err != nil {
+		t.Fatalf("Unexpected error listening %v", err)
+	}
+	defer l3.Close()
+
+	if _, err := tr.Listen(ctx, ":8080"); err == nil {
+		t.Fatal("Expected error binding to :8080 got nil")
+	}
+}

network/transport/options.go

@@ -0,0 +1,175 @@
+package transport
+
+import (
+	"context"
+	"crypto/tls"
+	"time"
+
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/tracer"
+)
+
+// Options struct holds the transport options
+type Options struct {
+	// Meter used for metrics
+	Meter meter.Meter
+	// Tracer used for tracing
+	Tracer tracer.Tracer
+	// Codec used for marshal/unmarshal messages
+	Codec codec.Codec
+	// Logger used for logging
+	Logger logger.Logger
+	// Context holds external options
+	Context context.Context
+	// TLSConfig holds tls.TLSConfig options
+	TLSConfig *tls.Config
+	// Name holds the transport name
+	Name string
+	// Addrs holds the transport addrs
+	Addrs []string
+	// Timeout holds the timeout
+	Timeout time.Duration
+}
+
+// NewOptions returns new options
+func NewOptions(opts ...Option) Options {
+	options := Options{
+		Logger:  logger.DefaultLogger,
+		Meter:   meter.DefaultMeter,
+		Tracer:  tracer.DefaultTracer,
+		Context: context.Background(),
+	}
+
+	for _, o := range opts {
+		o(&options)
+	}
+
+	return options
+}
+
+// DialOptions struct
+type DialOptions struct {
+	// Context holds the external options
+	Context context.Context
+	// Timeout holds the timeout
+	Timeout time.Duration
+	// Stream flag
+	Stream bool
+}
+
+// NewDialOptions returns new DialOptions
+func NewDialOptions(opts ...DialOption) DialOptions {
+	options := DialOptions{
+		Timeout: DefaultDialTimeout,
+		Context: context.Background(),
+	}
+
+	for _, o := range opts {
+		o(&options)
+	}
+
+	return options
+}
+
+// ListenOptions struct
+type ListenOptions struct {
+	// TODO: add tls options when listening
+	// Currently set in global options
+	// Context holds the external options
+	Context context.Context
+	// TLSConfig holds the *tls.Config options
+	TLSConfig *tls.Config
+}
+
+// NewListenOptions returns new ListenOptions
+func NewListenOptions(opts ...ListenOption) ListenOptions {
+	options := ListenOptions{
+		Context: context.Background(),
+	}
+
+	for _, o := range opts {
+		o(&options)
+	}
+
+	return options
+}
+
+// Addrs to use for transport
+func Addrs(addrs ...string) Option {
+	return func(o *Options) {
+		o.Addrs = addrs
+	}
+}
+
+// Logger sets the logger
+func Logger(l logger.Logger) Option {
+	return func(o *Options) {
+		o.Logger = l
+	}
+}
+
+// Meter sets the meter
+func Meter(m meter.Meter) Option {
+	return func(o *Options) {
+		o.Meter = m
+	}
+}
+
+// Context sets the context
+func Context(ctx context.Context) Option {
+	return func(o *Options) {
+		o.Context = ctx
+	}
+}
+
+// Codec sets the codec used for encoding where the transport
+// does not support message headers
+func Codec(c codec.Codec) Option {
+	return func(o *Options) {
+		o.Codec = c
+	}
+}
+
+// Timeout sets the timeout for Send/Recv execution
+func Timeout(t time.Duration) Option {
+	return func(o *Options) {
+		o.Timeout = t
+	}
+}
+
+// TLSConfig to be used for the transport.
+func TLSConfig(t *tls.Config) Option {
+	return func(o *Options) {
+		o.TLSConfig = t
+	}
+}
+
+// WithStream indicates whether this is a streaming connection
+func WithStream() DialOption {
+	return func(o *DialOptions) {
+		o.Stream = true
+	}
+}
+
+// WithTimeout used when dialling the remote side
+func WithTimeout(d time.Duration) DialOption {
+	return func(o *DialOptions) {
+		o.Timeout = d
+	}
+}
+
+// Tracer to be used for tracing
+func Tracer(t tracer.Tracer) Option {
+	return func(o *Options) {
+		o.Tracer = t
+	}
+}
+
+// Name sets the name
+func Name(n string) Option {
+	return func(o *Options) {
+		o.Name = n
+	}
+}

network/transport/transport.go

@@ -0,0 +1,63 @@
+// Package transport is an interface for synchronous connection based communication
+package transport // import "go.unistack.org/micro/v3/network/transport"
+
+import (
+	"context"
+	"time"
+
+	"go.unistack.org/micro/v3/metadata"
+)
+
+var (
+	// DefaultTransport is the global default transport
+	DefaultTransport Transport = NewTransport()
+	// DefaultDialTimeout the default dial timeout
+	DefaultDialTimeout = time.Second * 5
+)
+
+// Transport is an interface which is used for communication between
+// services. It uses connection based socket send/recv semantics and
+// has various implementations; http, grpc, quic.
+type Transport interface {
+	Init(...Option) error
+	Options() Options
+	Dial(ctx context.Context, addr string, opts ...DialOption) (Client, error)
+	Listen(ctx context.Context, addr string, opts ...ListenOption) (Listener, error)
+	String() string
+}
+
+// Message is used to transfer data
+type Message struct {
+	Header metadata.Metadata
+	Body   []byte
+}
+
+// Socket bastraction interface
+type Socket interface {
+	Recv(*Message) error
+	Send(*Message) error
+	Close() error
+	Local() string
+	Remote() string
+}
+
+// Client is the socket owner
+type Client interface {
+	Socket
+}
+
+// Listener is the interface for stream oriented messaging
+type Listener interface {
+	Addr() string
+	Close() error
+	Accept(func(Socket)) error
+}
+
+// Option is the option signature
+type Option func(*Options)
+
+// DialOption is the option signature
+type DialOption func(*DialOptions)
+
+// ListenOption is the option signature
+type ListenOption func(*ListenOptions)

network/tunnel/broker/broker.go

@@ -0,0 +1,356 @@
+// Package broker is a tunnel broker
+package broker // import "go.unistack.org/micro/v3/network/tunnel/broker"
+
+import (
+	"context"
+	"fmt"
+
+	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/network/transport"
+	"go.unistack.org/micro/v3/network/tunnel"
+)
+
+type tunBroker struct {
+	tunnel tunnel.Tunnel
+	opts   broker.Options
+}
+
+type tunSubscriber struct {
+	listener tunnel.Listener
+	handler  broker.Handler
+	closed   chan bool
+	topic    string
+	opts     broker.SubscribeOptions
+}
+
+type tunBatchSubscriber struct {
+	listener tunnel.Listener
+	handler  broker.BatchHandler
+	closed   chan bool
+	topic    string
+	opts     broker.SubscribeOptions
+}
+
+type tunEvent struct {
+	err     error
+	message *broker.Message
+	topic   string
+}
+
+// used to access tunnel from options context
+type (
+	tunnelKey  struct{}
+	tunnelAddr struct{}
+)
+
+func (t *tunBroker) Init(opts ...broker.Option) error {
+	for _, o := range opts {
+		o(&t.opts)
+	}
+	return nil
+}
+
+func (t *tunBroker) Name() string {
+	return t.opts.Name
+}
+
+func (t *tunBroker) Options() broker.Options {
+	return t.opts
+}
+
+func (t *tunBroker) Address() string {
+	return t.tunnel.Address()
+}
+
+func (t *tunBroker) Connect(ctx context.Context) error {
+	return t.tunnel.Connect(ctx)
+}
+
+func (t *tunBroker) Disconnect(ctx context.Context) error {
+	return t.tunnel.Close(ctx)
+}
+
+func (t *tunBroker) BatchPublish(ctx context.Context, msgs []*broker.Message, opts ...broker.PublishOption) error {
+	// TODO: this is probably inefficient, we might want to just maintain an open connection
+	// it may be easier to add broadcast to the tunnel
+	topicMap := make(map[string]tunnel.Session)
+
+	var err error
+	for _, msg := range msgs {
+		topic, _ := msg.Header.Get(metadata.HeaderTopic)
+		c, ok := topicMap[topic]
+		if !ok {
+			c, err = t.tunnel.Dial(ctx, topic, tunnel.DialMode(tunnel.Multicast))
+			if err != nil {
+				return err
+			}
+			defer c.Close()
+			topicMap[topic] = c
+		}
+
+		if err = c.Send(&transport.Message{
+			Header: msg.Header,
+			Body:   msg.Body,
+		}); err != nil {
+			//	msg.SetError(err)
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (t *tunBroker) Publish(ctx context.Context, topic string, m *broker.Message, opts ...broker.PublishOption) error {
+	// TODO: this is probably inefficient, we might want to just maintain an open connection
+	// it may be easier to add broadcast to the tunnel
+	c, err := t.tunnel.Dial(ctx, topic, tunnel.DialMode(tunnel.Multicast))
+	if err != nil {
+		return err
+	}
+	defer c.Close()
+
+	return c.Send(&transport.Message{
+		Header: m.Header,
+		Body:   m.Body,
+	})
+}
+
+func (t *tunBroker) BatchSubscribe(ctx context.Context, topic string, h broker.BatchHandler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
+	l, err := t.tunnel.Listen(ctx, topic, tunnel.ListenMode(tunnel.Multicast))
+	if err != nil {
+		return nil, err
+	}
+
+	tunSub := &tunBatchSubscriber{
+		topic:    topic,
+		handler:  h,
+		opts:     broker.NewSubscribeOptions(opts...),
+		closed:   make(chan bool),
+		listener: l,
+	}
+
+	// start processing
+	go tunSub.run()
+
+	return tunSub, nil
+}
+
+func (t *tunBroker) Subscribe(ctx context.Context, topic string, h broker.Handler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
+	l, err := t.tunnel.Listen(ctx, topic, tunnel.ListenMode(tunnel.Multicast))
+	if err != nil {
+		return nil, err
+	}
+
+	tunSub := &tunSubscriber{
+		topic:    topic,
+		handler:  h,
+		opts:     broker.NewSubscribeOptions(opts...),
+		closed:   make(chan bool),
+		listener: l,
+	}
+
+	// start processing
+	go tunSub.run()
+
+	return tunSub, nil
+}
+
+func (t *tunBroker) String() string {
+	return "tunnel"
+}
+
+func (t *tunBatchSubscriber) run() {
+	for {
+		// accept a new connection
+		c, err := t.listener.Accept()
+		if err != nil {
+			select {
+			case <-t.closed:
+				return
+			default:
+				continue
+			}
+		}
+
+		// receive message
+		m := new(transport.Message)
+		if err := c.Recv(m); err != nil {
+			if logger.V(logger.ErrorLevel) {
+				logger.Error(t.opts.Context, err.Error())
+			}
+			if err = c.Close(); err != nil {
+				if logger.V(logger.ErrorLevel) {
+					logger.Error(t.opts.Context, err.Error())
+				}
+			}
+			continue
+		}
+
+		// close the connection
+		c.Close()
+
+		evts := broker.Events{&tunEvent{
+			topic: t.topic,
+			message: &broker.Message{
+				Header: m.Header,
+				Body:   m.Body,
+			},
+		}}
+		// handle the message
+		go func() {
+			_ = t.handler(evts)
+		}()
+
+	}
+}
+
+func (t *tunSubscriber) run() {
+	for {
+		// accept a new connection
+		c, err := t.listener.Accept()
+		if err != nil {
+			select {
+			case <-t.closed:
+				return
+			default:
+				continue
+			}
+		}
+
+		// receive message
+		m := new(transport.Message)
+		if err := c.Recv(m); err != nil {
+			if logger.V(logger.ErrorLevel) {
+				logger.Error(t.opts.Context, err.Error())
+			}
+			if err = c.Close(); err != nil {
+				if logger.V(logger.ErrorLevel) {
+					logger.Error(t.opts.Context, err.Error())
+				}
+			}
+			continue
+		}
+
+		// close the connection
+		c.Close()
+
+		// handle the message
+		go func() {
+			_ = t.handler(&tunEvent{
+				topic: t.topic,
+				message: &broker.Message{
+					Header: m.Header,
+					Body:   m.Body,
+				},
+			})
+		}()
+	}
+}
+
+func (t *tunBatchSubscriber) Options() broker.SubscribeOptions {
+	return t.opts
+}
+
+func (t *tunBatchSubscriber) Topic() string {
+	return t.topic
+}
+
+func (t *tunBatchSubscriber) Unsubscribe(ctx context.Context) error {
+	select {
+	case <-t.closed:
+		return nil
+	default:
+		close(t.closed)
+		return t.listener.Close()
+	}
+}
+
+func (t *tunSubscriber) Options() broker.SubscribeOptions {
+	return t.opts
+}
+
+func (t *tunSubscriber) Topic() string {
+	return t.topic
+}
+
+func (t *tunSubscriber) Unsubscribe(ctx context.Context) error {
+	select {
+	case <-t.closed:
+		return nil
+	default:
+		close(t.closed)
+		return t.listener.Close()
+	}
+}
+
+func (t *tunEvent) Topic() string {
+	return t.topic
+}
+
+func (t *tunEvent) Message() *broker.Message {
+	return t.message
+}
+
+func (t *tunEvent) Ack() error {
+	return nil
+}
+
+func (t *tunEvent) Error() error {
+	return t.err
+}
+
+func (t *tunEvent) SetError(err error) {
+	t.err = err
+}
+
+// NewBroker returns new tunnel broker
+func NewBroker(opts ...broker.Option) (broker.Broker, error) {
+	options := broker.NewOptions(opts...)
+
+	t, ok := options.Context.Value(tunnelKey{}).(tunnel.Tunnel)
+	if !ok {
+		return nil, fmt.Errorf("tunnel not set")
+	}
+
+	a, ok := options.Context.Value(tunnelAddr{}).(string)
+	if ok {
+		// initialise address
+		if err := t.Init(tunnel.Address(a)); err != nil {
+			return nil, err
+		}
+	}
+
+	if len(options.Addrs) > 0 {
+		// initialise nodes
+		if err := t.Init(tunnel.Nodes(options.Addrs...)); err != nil {
+			return nil, err
+		}
+	}
+
+	return &tunBroker{
+		opts:   options,
+		tunnel: t,
+	}, nil
+}
+
+// WithAddress sets the tunnel address
+func WithAddress(a string) broker.Option {
+	return func(o *broker.Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, tunnelAddr{}, a)
+	}
+}
+
+// WithTunnel sets the internal tunnel
+func WithTunnel(t tunnel.Tunnel) broker.Option {
+	return func(o *broker.Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, tunnelKey{}, t)
+	}
+}

network/tunnel/options.go

@@ -0,0 +1,192 @@
+package tunnel
+
+import (
+	"time"
+
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/network/transport"
+	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v3/util/id"
+)
+
+var (
+	// DefaultAddress is default tunnel bind address
+	DefaultAddress = ":0"
+	// DefaultToken the shared default token
+	DefaultToken = "go.micro.tunnel"
+)
+
+// Option func signature
+type Option func(*Options)
+
+// Options provides network configuration options
+type Options struct {
+	// Logger used for logging
+	Logger logger.Logger
+	// Meter used for metrics
+	Meter meter.Meter
+	// Tracer used for tracing
+	Tracer tracer.Tracer
+	// Transport used for communication
+	Transport transport.Transport
+	// Token the shared auth token
+	Token string
+	// Name holds the tunnel name
+	Name string
+	// ID holds the tunnel id
+	ID string
+	// Address holds the tunnel address
+	Address string
+	// Nodes holds the tunnel nodes
+	Nodes []string
+}
+
+// DialOption func
+type DialOption func(*DialOptions)
+
+// DialOptions provides dial options
+type DialOptions struct {
+	// Link specifies the link to use
+	Link string
+	// specify mode of the session
+	Mode Mode
+	// Wait for connection to be accepted
+	Wait bool
+	// the dial timeout
+	Timeout time.Duration
+}
+
+// ListenOption func
+type ListenOption func(*ListenOptions)
+
+// ListenOptions provides listen options
+type ListenOptions struct {
+	// Mode specify mode of the session
+	Mode Mode
+	// Timeout the read timeout
+	Timeout time.Duration
+}
+
+// ID sets the tunnel id
+func ID(id string) Option {
+	return func(o *Options) {
+		o.ID = id
+	}
+}
+
+// Logger sets the logger
+func Logger(l logger.Logger) Option {
+	return func(o *Options) {
+		o.Logger = l
+	}
+}
+
+// Meter sets the meter
+func Meter(m meter.Meter) Option {
+	return func(o *Options) {
+		o.Meter = m
+	}
+}
+
+// Address sets the tunnel address
+func Address(a string) Option {
+	return func(o *Options) {
+		o.Address = a
+	}
+}
+
+// Nodes specify remote network nodes
+func Nodes(n ...string) Option {
+	return func(o *Options) {
+		o.Nodes = n
+	}
+}
+
+// Token sets the shared token for auth
+func Token(t string) Option {
+	return func(o *Options) {
+		o.Token = t
+	}
+}
+
+// Transport listens for incoming connections
+func Transport(t transport.Transport) Option {
+	return func(o *Options) {
+		o.Transport = t
+	}
+}
+
+// ListenMode option
+func ListenMode(m Mode) ListenOption {
+	return func(o *ListenOptions) {
+		o.Mode = m
+	}
+}
+
+// ListenTimeout for reads and writes on the listener session
+func ListenTimeout(t time.Duration) ListenOption {
+	return func(o *ListenOptions) {
+		o.Timeout = t
+	}
+}
+
+// DialMode multicast sets the multicast option to send only to those mapped
+func DialMode(m Mode) DialOption {
+	return func(o *DialOptions) {
+		o.Mode = m
+	}
+}
+
+// DialTimeout sets the dial timeout of the connection
+func DialTimeout(t time.Duration) DialOption {
+	return func(o *DialOptions) {
+		o.Timeout = t
+	}
+}
+
+// DialLink specifies the link to pin this connection to.
+// This is not applicable if the multicast option is set.
+func DialLink(id string) DialOption {
+	return func(o *DialOptions) {
+		o.Link = id
+	}
+}
+
+// DialWait specifies whether to wait for the connection
+// to be accepted before returning the session
+func DialWait(b bool) DialOption {
+	return func(o *DialOptions) {
+		o.Wait = b
+	}
+}
+
+// NewOptions returns router default options with filled values
+func NewOptions(opts ...Option) Options {
+	options := Options{
+		ID:      id.Must(),
+		Address: DefaultAddress,
+		Token:   DefaultToken,
+		Logger:  logger.DefaultLogger,
+		Meter:   meter.DefaultMeter,
+		Tracer:  tracer.DefaultTracer,
+	}
+	for _, o := range opts {
+		o(&options)
+	}
+	return options
+}
+
+// Tracer to be used for tracing
+func Tracer(t tracer.Tracer) Option {
+	return func(o *Options) {
+		o.Tracer = t
+	}
+}
+
+// Name sets the name
+func Name(n string) Option {
+	return func(o *Options) {
+		o.Name = n
+	}
+}

network/tunnel/transport/listener.go

@@ -0,0 +1,30 @@
+package transport
+
+import (
+	"go.unistack.org/micro/v3/network/transport"
+	"go.unistack.org/micro/v3/network/tunnel"
+)
+
+type tunListener struct {
+	l tunnel.Listener
+}
+
+func (t *tunListener) Addr() string {
+	return t.l.Channel()
+}
+
+func (t *tunListener) Close() error {
+	return t.l.Close()
+}
+
+func (t *tunListener) Accept(fn func(socket transport.Socket)) error {
+	for {
+		// accept connection
+		c, err := t.l.Accept()
+		if err != nil {
+			return err
+		}
+		// execute the function
+		go fn(c)
+	}
+}

network/tunnel/transport/transport.go

@@ -0,0 +1,113 @@
+// Package transport provides a tunnel transport
+package transport // import "go.unistack.org/micro/v3/network/tunnel/transport"
+
+import (
+	"context"
+	"fmt"
+
+	"go.unistack.org/micro/v3/network/transport"
+	"go.unistack.org/micro/v3/network/tunnel"
+)
+
+type tunTransport struct {
+	tunnel  tunnel.Tunnel
+	options transport.Options
+}
+
+type tunnelKey struct{}
+
+type transportKey struct{}
+
+func (t *tunTransport) Init(opts ...transport.Option) error {
+	for _, o := range opts {
+		o(&t.options)
+	}
+
+	// close the existing tunnel
+	if t.tunnel != nil {
+		t.tunnel.Close(context.TODO())
+	}
+
+	// get the tunnel
+	tun, ok := t.options.Context.Value(tunnelKey{}).(tunnel.Tunnel)
+	if !ok {
+		return fmt.Errorf("tunnel not set")
+	}
+
+	// get the transport
+	tr, ok := t.options.Context.Value(transportKey{}).(transport.Transport)
+	if ok {
+		_ = tun.Init(tunnel.Transport(tr))
+	}
+
+	// set the tunnel
+	t.tunnel = tun
+
+	return nil
+}
+
+func (t *tunTransport) Dial(ctx context.Context, addr string, opts ...transport.DialOption) (transport.Client, error) {
+	if err := t.tunnel.Connect(ctx); err != nil {
+		return nil, err
+	}
+
+	c, err := t.tunnel.Dial(ctx, addr)
+	if err != nil {
+		return nil, err
+	}
+
+	return c, nil
+}
+
+func (t *tunTransport) Listen(ctx context.Context, addr string, opts ...transport.ListenOption) (transport.Listener, error) {
+	if err := t.tunnel.Connect(ctx); err != nil {
+		return nil, err
+	}
+
+	l, err := t.tunnel.Listen(ctx, addr)
+	if err != nil {
+		return nil, err
+	}
+
+	return &tunListener{l}, nil
+}
+
+func (t *tunTransport) Options() transport.Options {
+	return t.options
+}
+
+func (t *tunTransport) String() string {
+	return "tunnel"
+}
+
+// NewTransport honours the initialiser used in
+func NewTransport(opts ...transport.Option) transport.Transport {
+	t := &tunTransport{
+		options: transport.Options{},
+	}
+
+	// initialise
+	// t.Init(opts...)
+
+	return t
+}
+
+// WithTunnel sets the internal tunnel
+func WithTunnel(t tunnel.Tunnel) transport.Option {
+	return func(o *transport.Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, tunnelKey{}, t)
+	}
+}
+
+// WithTransport sets the internal transport
+func WithTransport(t transport.Transport) transport.Option {
+	return func(o *transport.Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, transportKey{}, t)
+	}
+}

network/tunnel/tunnel.go

@@ -0,0 +1,106 @@
+// Package tunnel provides gre network tunnelling
+package tunnel // import "go.unistack.org/micro/v3/network/transport/tunnel"
+
+import (
+	"context"
+	"errors"
+	"time"
+
+	"go.unistack.org/micro/v3/network/transport"
+)
+
+// DefaultTunnel contains default tunnel implementation
+var DefaultTunnel Tunnel
+
+const (
+	// Unicast send over one link
+	Unicast Mode = iota
+	// Multicast send to all channel listeners
+	Multicast
+	// Broadcast send to all links
+	Broadcast
+)
+
+var (
+	// DefaultDialTimeout is the dial timeout if none is specified
+	DefaultDialTimeout = time.Second * 5
+	// ErrDialTimeout is returned by a call to Dial where the timeout occurs
+	ErrDialTimeout = errors.New("dial timeout")
+	// ErrDiscoverChan is returned when we failed to receive the "announce" back from a discovery
+	ErrDiscoverChan = errors.New("failed to discover channel")
+	// ErrLinkNotFound is returned when a link is specified at dial time and does not exist
+	ErrLinkNotFound = errors.New("link not found")
+	// ErrLinkDisconnected is returned when a link we attempt to send to is disconnected
+	ErrLinkDisconnected = errors.New("link not connected")
+	// ErrLinkLoopback is returned when attempting to send an outbound message over loopback link
+	ErrLinkLoopback = errors.New("link is loopback")
+	// ErrLinkRemote is returned when attempting to send a loopback message over remote link
+	ErrLinkRemote = errors.New("link is remote")
+	// ErrReadTimeout is a timeout on session.Recv
+	ErrReadTimeout = errors.New("read timeout")
+	// ErrDecryptingData is for when theres a nonce error
+	ErrDecryptingData = errors.New("error decrypting data")
+)
+
+// Mode of the session
+type Mode uint8
+
+// Tunnel creates a gre tunnel on top of the micro/transport.
+// It establishes multiple streams using the Micro-Tunnel-Channel header
+// and Micro-Tunnel-Session header. The tunnel id is a hash of
+// the address being requested.
+type Tunnel interface {
+	// Init initializes tunnel with options
+	Init(opts ...Option) error
+	// Address returns the address the tunnel is listening on
+	Address() string
+	// Connect connects the tunnel
+	Connect(ctx context.Context) error
+	// Close closes the tunnel
+	Close(ctx context.Context) error
+	// Links returns all the links the tunnel is connected to
+	Links() []Link
+	// Dial allows a client to connect to a channel
+	Dial(ctx context.Context, channel string, opts ...DialOption) (Session, error)
+	// Listen allows to accept connections on a channel
+	Listen(ctx context.Context, channel string, opts ...ListenOption) (Listener, error)
+	// String returns the name of the tunnel implementation
+	String() string
+}
+
+// Link represents internal links to the tunnel
+type Link interface {
+	// Id returns the link unique Id
+	Id() string
+	// Delay is the current load on the link (lower is better)
+	Delay() int64
+	// Length returns the roundtrip time as nanoseconds (lower is better)
+	Length() int64
+	// Current transfer rate as bits per second (lower is better)
+	Rate() float64
+	// Is this a loopback link
+	Loopback() bool
+	// State of the link: connected/closed/error
+	State() string
+	// honours transport socket
+	transport.Socket
+}
+
+// Listener provides similar constructs to the transport.Listener
+type Listener interface {
+	Accept() (Session, error)
+	Channel() string
+	Close() error
+}
+
+// Session is a unique session created when dialling or accepting connections on the tunnel
+type Session interface {
+	// The unique session id
+	Id() string
+	// The channel name
+	Channel() string
+	// The link the session is on
+	Link() string
+	// a transport socket
+	transport.Socket
+}

options.go

@@ -5,18 +5,17 @@ import (
 	"fmt"
 	"time"
 
-	"go.unistack.org/micro/v4/broker"
-	"go.unistack.org/micro/v4/client"
-	"go.unistack.org/micro/v4/config"
-	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v4/register"
-	"go.unistack.org/micro/v4/router"
-	"go.unistack.org/micro/v4/server"
-	"go.unistack.org/micro/v4/store"
-	"go.unistack.org/micro/v4/tracer"
+	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/config"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v3/router"
+	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v3/store"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // Options for micro service
@@ -91,7 +90,33 @@ type Option func(*Options) error
 // Broker to be used for client and server
 func Broker(b broker.Broker, opts ...BrokerOption) Option {
 	return func(o *Options) error {
-		o.Brokers = []broker.Broker{b}
+		var err error
+		bopts := brokerOptions{}
+		for _, opt := range opts {
+			opt(&bopts)
+		}
+		all := false
+		if len(opts) == 0 {
+			all = true
+		}
+		for _, srv := range o.Servers {
+			for _, os := range bopts.servers {
+				if srv.Name() == os || all {
+					if err = srv.Init(server.Broker(b)); err != nil {
+						return err
+					}
+				}
+			}
+		}
+		for _, cli := range o.Clients {
+			for _, oc := range bopts.clients {
+				if cli.Name() == oc || all {
+					if err = cli.Init(client.Broker(b)); err != nil {
+						return err
+					}
+				}
+			}
+		}
 		return nil
 	}
 }
@@ -202,7 +227,7 @@ func Logger(l logger.Logger, opts ...LoggerOption) Option {
 		for _, srv := range o.Servers {
 			for _, os := range lopts.servers {
 				if srv.Name() == os || all {
-					if err = srv.Init(options.Logger(l)); err != nil {
+					if err = srv.Init(server.Logger(l)); err != nil {
 						return err
 					}
 				}
@@ -211,7 +236,7 @@ func Logger(l logger.Logger, opts ...LoggerOption) Option {
 		for _, cli := range o.Clients {
 			for _, oc := range lopts.clients {
 				if cli.Name() == oc || all {
-					if err = cli.Init(options.Logger(l)); err != nil {
+					if err = cli.Init(client.Logger(l)); err != nil {
 						return err
 					}
 				}
@@ -220,7 +245,7 @@ func Logger(l logger.Logger, opts ...LoggerOption) Option {
 		for _, brk := range o.Brokers {
 			for _, ob := range lopts.brokers {
 				if brk.Name() == ob || all {
-					if err = brk.Init(options.Logger(l)); err != nil {
+					if err = brk.Init(broker.Logger(l)); err != nil {
 						return err
 					}
 				}
@@ -238,7 +263,7 @@ func Logger(l logger.Logger, opts ...LoggerOption) Option {
 		for _, str := range o.Stores {
 			for _, or := range lopts.stores {
 				if str.Name() == or || all {
-					if err = str.Init(options.Logger(l)); err != nil {
+					if err = str.Init(store.Logger(l)); err != nil {
 						return err
 					}
 				}
@@ -247,7 +272,7 @@ func Logger(l logger.Logger, opts ...LoggerOption) Option {
 		for _, mtr := range o.Meters {
 			for _, or := range lopts.meters {
 				if mtr.Name() == or || all {
-					if err = mtr.Init(options.Logger(l)); err != nil {
+					if err = mtr.Init(meter.Logger(l)); err != nil {
 						return err
 					}
 				}
@@ -256,7 +281,7 @@ func Logger(l logger.Logger, opts ...LoggerOption) Option {
 		for _, trc := range o.Tracers {
 			for _, ot := range lopts.tracers {
 				if trc.Name() == ot || all {
-					if err = trc.Init(options.Logger(l)); err != nil {
+					if err = trc.Init(tracer.Logger(l)); err != nil {
 						return err
 					}
 				}
@@ -330,7 +355,7 @@ func Register(r register.Register, opts ...RegisterOption) Option {
 		for _, srv := range o.Servers {
 			for _, os := range ropts.servers {
 				if srv.Name() == os || all {
-					if err = srv.Init(options.Register(r)); err != nil {
+					if err = srv.Init(server.Register(r)); err != nil {
 						return err
 					}
 				}
@@ -339,7 +364,7 @@ func Register(r register.Register, opts ...RegisterOption) Option {
 		for _, brk := range o.Brokers {
 			for _, os := range ropts.brokers {
 				if brk.Name() == os || all {
-					if err = brk.Init(options.Register(r)); err != nil {
+					if err = brk.Init(broker.Register(r)); err != nil {
 						return err
 					}
 				}
@@ -396,7 +421,7 @@ func Tracer(t tracer.Tracer, opts ...TracerOption) Option {
 		for _, srv := range o.Servers {
 			for _, os := range topts.servers {
 				if srv.Name() == os || all {
-					if err = srv.Init(options.Tracer(t)); err != nil {
+					if err = srv.Init(server.Tracer(t)); err != nil {
 						return err
 					}
 				}
@@ -405,7 +430,7 @@ func Tracer(t tracer.Tracer, opts ...TracerOption) Option {
 		for _, cli := range o.Clients {
 			for _, os := range topts.clients {
 				if cli.Name() == os || all {
-					if err = cli.Init(options.Tracer(t)); err != nil {
+					if err = cli.Init(client.Tracer(t)); err != nil {
 						return err
 					}
 				}
@@ -414,7 +439,7 @@ func Tracer(t tracer.Tracer, opts ...TracerOption) Option {
 		for _, str := range o.Stores {
 			for _, os := range topts.stores {
 				if str.Name() == os || all {
-					if err = str.Init(options.Tracer(t)); err != nil {
+					if err = str.Init(store.Tracer(t)); err != nil {
 						return err
 					}
 				}
@@ -423,7 +448,7 @@ func Tracer(t tracer.Tracer, opts ...TracerOption) Option {
 		for _, brk := range o.Brokers {
 			for _, os := range topts.brokers {
 				if brk.Name() == os || all {
-					if err = brk.Init(options.Tracer(t)); err != nil {
+					if err = brk.Init(broker.Tracer(t)); err != nil {
 						return err
 					}
 				}
@@ -522,7 +547,7 @@ func Router(r router.Router, opts ...RouterOption) Option {
 		for _, cli := range o.Clients {
 			for _, os := range ropts.clients {
 				if cli.Name() == os || all {
-					if err = cli.Init(options.Router(r)); err != nil {
+					if err = cli.Init(client.Router(r)); err != nil {
 						return err
 					}
 				}
@@ -557,7 +582,7 @@ func Address(addr string) Option {
 		default:
 			return fmt.Errorf("cant set same address for multiple servers")
 		}
-		return o.Servers[0].Init(options.Address(addr))
+		return o.Servers[0].Init(server.Address(addr))
 	}
 }
 

options/hooks.go

@@ -1,4 +1,4 @@
-package options // import "go.unistack.org/micro/v4/options"
+package options // import "go.unistack.org/micro/v3/options"
 
 // Hook func interface
 type Hook interface{}

options/options.go

@@ -1,221 +0,0 @@
-package options
-
-import (
-	"context"
-	"crypto/tls"
-	"reflect"
-	"time"
-
-	"go.unistack.org/micro/v4/metadata"
-	rutil "go.unistack.org/micro/v4/util/reflect"
-)
-
-// Option func signature
-type Option func(interface{}) error
-
-// Set assign value to struct by its path
-func Set(src interface{}, dst interface{}, path string) error {
-	return rutil.SetFieldByPath(src, dst, path)
-}
-
-// Get returns value from struct by its path
-func Get(src interface{}, path string) (interface{}, error) {
-	return rutil.StructFieldByPath(src, path)
-}
-
-// Name set Name value
-func Name(v ...string) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Name")
-	}
-}
-
-// Address set Address value to single string or slice of strings
-func Address(v ...string) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Address")
-	}
-}
-
-// Broker set Broker value
-func Broker(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Broker")
-	}
-}
-
-// Logger set Logger value
-func Logger(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Logger")
-	}
-}
-
-// Meter set Meter value
-func Meter(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Meter")
-	}
-}
-
-// Tracer set Tracer value
-func Tracer(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Tracer")
-	}
-}
-
-// Store set Store value
-func Store(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Store")
-	}
-}
-
-// Register set Register value
-func Register(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Register")
-	}
-}
-
-// Router set Router value
-func Router(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Router")
-	}
-}
-
-// Codec set Codec value
-func Codec(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Codec")
-	}
-}
-
-// Client set Client value
-func Client(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Client")
-	}
-}
-
-// Codecs to be used to encode/decode requests for a given content type
-func Codecs(ct string, v interface{}) Option {
-	return func(src interface{}) error {
-		cm, err := Get(src, ".Codecs")
-		if err != nil {
-			return err
-		} else if rutil.IsZero(cm) {
-			cm = reflect.MakeMap(reflect.TypeOf(cm)).Interface()
-		}
-		cv := reflect.ValueOf(cm)
-		cv.SetMapIndex(reflect.ValueOf(ct), reflect.ValueOf(v))
-		return Set(src, cv.Interface(), ".Codecs")
-	}
-}
-
-// Context set Context value
-func Context(v context.Context) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Context")
-	}
-}
-
-// TLSConfig set TLSConfig value
-func TLSConfig(v *tls.Config) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".TLSConfig")
-	}
-}
-
-func ContextOption(k, v interface{}) Option {
-	return func(src interface{}) error {
-		ctx, err := Get(src, ".Context")
-		if err != nil {
-			return err
-		}
-		if ctx == nil {
-			ctx = context.Background()
-		}
-		err = Set(src, context.WithValue(ctx.(context.Context), k, v), ".Context")
-		return err
-	}
-}
-
-// ContentType pass ContentType for message data
-func ContentType(ct string) Option {
-	return func(src interface{}) error {
-		return Set(src, ct, ".ContentType")
-	}
-}
-
-// Metadata pass additional metadata
-func Metadata(md ...any) Option {
-	var result metadata.Metadata
-	if len(md) == 1 {
-		switch vt := md[0].(type) {
-		case metadata.Metadata:
-			result = metadata.Copy(vt)
-		case map[string]string:
-			result = make(metadata.Metadata, len(vt))
-			for k, v := range vt {
-				result.Set(k, v)
-			}
-		case map[string][]string:
-			result = metadata.Copy(vt)
-		default:
-			result = metadata.New(0)
-		}
-	} else {
-		result = metadata.New(len(md) / 2)
-		for idx := 0; idx <= len(md)/2; idx += 2 {
-			k, ok := md[idx].(string)
-			switch vt := md[idx+1].(type) {
-			case string:
-				if ok {
-					result.Set(k, vt)
-				}
-			case []string:
-				if ok {
-					result.Append(k, vt...)
-				}
-			}
-		}
-	}
-
-	return func(src interface{}) error {
-		return Set(src, result, ".Metadata")
-	}
-}
-
-// Namespace to use
-func Namespace(ns string) Option {
-	return func(src interface{}) error {
-		return Set(src, ns, ".Namespace")
-	}
-}
-
-// Labels sets the labels
-func Labels(ls ...interface{}) Option {
-	return func(src interface{}) error {
-		v, err := Get(src, ".Labels")
-		if err != nil {
-			return err
-		} else if rutil.IsZero(v) {
-			v = reflect.MakeSlice(reflect.TypeOf(v), 0, len(ls)).Interface()
-		}
-		cv := reflect.ValueOf(v)
-		for _, l := range ls {
-			cv = reflect.Append(cv, reflect.ValueOf(l))
-		}
-		return Set(src, cv.Interface(), ".Labels")
-	}
-}
-
-// Timeout pass timeout time.Duration
-func Timeout(td time.Duration) Option {
-	return func(src interface{}) error {
-		return Set(src, td, ".Timeout")
-	}
-}

options/options_test.go

@@ -1,149 +0,0 @@
-package options_test
-
-import (
-	"testing"
-
-	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v4/util/reflect"
-)
-
-func TestAddress(t *testing.T) {
-	var err error
-
-	type s struct {
-		Address []string
-	}
-
-	src := &s{}
-	var opts []options.Option
-	opts = append(opts, options.Address("host:port"))
-
-	for _, o := range opts {
-		if err = o(src); err != nil {
-			t.Fatal(err)
-		}
-	}
-
-	if src.Address[0] != "host:port" {
-		t.Fatal("failed to set Address")
-	}
-}
-
-func TestCodecs(t *testing.T) {
-	var err error
-
-	type s struct {
-		Codecs map[string]codec.Codec
-	}
-
-	src := &s{}
-	var opts []options.Option
-	c := codec.NewCodec()
-	opts = append(opts, options.Codecs("text/html", c))
-
-	for _, o := range opts {
-		if err = o(src); err != nil {
-			t.Fatal(err)
-		}
-	}
-
-	for k, v := range src.Codecs {
-		if k != "text/html" || v != c {
-			continue
-		}
-		return
-	}
-
-	t.Fatalf("failed to set Codecs")
-}
-
-func TestLabels(t *testing.T) {
-	type str1 struct {
-		Labels []string
-	}
-	type str2 struct {
-		Labels []interface{}
-	}
-
-	x1 := &str1{}
-
-	if err := options.Labels("one", "two")(x1); err != nil {
-		t.Fatal(err)
-	}
-	if len(x1.Labels) != 2 {
-		t.Fatal("failed to set labels")
-	}
-	x2 := &str2{}
-	if err := options.Labels("key", "val")(x2); err != nil {
-		t.Fatal(err)
-	}
-	if len(x2.Labels) != 2 {
-		t.Fatal("failed to set labels")
-	}
-	if x2.Labels[0] != "key" {
-		t.Fatal("failed to set labels")
-	}
-}
-
-func TestMetadataAny(t *testing.T) {
-	type s struct {
-		Metadata metadata.Metadata
-	}
-
-	testCases := []struct {
-		Name     string
-		Data     any
-		Expected metadata.Metadata
-	}{
-		{
-			"strings_even",
-			[]any{"Strkey1", []string{"val1"}, "Strkey2", []string{"val2"}},
-			metadata.Pairs("Strkey1", "val1", "Strkey2", "val2"),
-		},
-		{
-			"strings_odd",
-			[]any{"key1", "val1", "key2"},
-			metadata.Pairs("Key1", "val1"),
-		},
-		{
-			Name: "map",
-			Data: map[string][]string{
-				"Mapkey1": {"val1"},
-				"Mapkey2": {"val2"},
-			},
-			Expected: metadata.Metadata{
-				"Mapkey1": []string{"val1"},
-				"Mapkey2": []string{"val2"},
-			},
-		},
-		{
-			"metadata.Metadata",
-			metadata.Pairs("key1", "val1", "key2", "val2"),
-			metadata.Pairs("Key1", "val1", "Key2", "val2"),
-		},
-	}
-
-	for _, tt := range testCases {
-		t.Run(tt.Name, func(t *testing.T) {
-			src := &s{}
-			var opts []options.Option
-			switch valData := tt.Data.(type) {
-			case []any:
-				opts = append(opts, options.Metadata(valData...))
-			case map[string]string, map[string][]string, metadata.Metadata:
-				opts = append(opts, options.Metadata(valData))
-			}
-
-			for _, o := range opts {
-				if err := o(src); err != nil {
-					t.Fatal(err)
-				}
-				if !reflect.Equal(tt.Expected, src.Metadata) {
-					t.Fatalf("expected: %v, actual: %v", tt.Expected, src.Metadata)
-				}
-			}
-		})
-	}
-}

profiler/http/http.go

@@ -1,5 +1,5 @@
 // Package http enables the http profiler
-package http // import "go.unistack.org/micro/v4/profiler/http"
+package http // import "go.unistack.org/micro/v3/profiler/http"
 
 import (
 	"context"
@@ -7,7 +7,7 @@ import (
 	"net/http/pprof"
 	"sync"
 
-	profile "go.unistack.org/micro/v4/profiler"
+	profile "go.unistack.org/micro/v3/profiler"
 )
 
 type httpProfile struct {

profiler/pprof/pprof.go

@@ -1,5 +1,5 @@
 // Package pprof provides a pprof profiler which writes output to /tmp/[name].{cpu,mem}.pprof
-package pprof // import "go.unistack.org/micro/v4/profiler/pprof"
+package pprof // import "go.unistack.org/micro/v3/profiler/pprof"
 
 import (
 	"os"
@@ -9,7 +9,7 @@ import (
 	"sync"
 	"time"
 
-	profile "go.unistack.org/micro/v4/profiler"
+	profile "go.unistack.org/micro/v3/profiler"
 )
 
 type profiler struct {

profiler/profile.go

@@ -1,5 +1,5 @@
 // Package profiler is for profilers
-package profiler // import "go.unistack.org/micro/v4/profiler"
+package profiler // import "go.unistack.org/micro/v3/profiler"
 
 // Profiler interface
 type Profiler interface {

proxy/options.go

@@ -0,0 +1,98 @@
+// Package proxy is a transparent proxy built on the micro/server
+package proxy
+
+import (
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/router"
+	"go.unistack.org/micro/v3/tracer"
+)
+
+// Options for proxy
+type Options struct {
+	// Tracer used for tracing
+	Tracer tracer.Tracer
+	// Client for communication
+	Client client.Client
+	// Router for routing
+	Router router.Router
+	// Logger used for logging
+	Logger logger.Logger
+	// Meter used for metrics
+	Meter meter.Meter
+	// Links holds the communication links
+	Links map[string]client.Client
+	// Endpoint holds the destination address
+	Endpoint string
+}
+
+// Option func signature
+type Option func(o *Options)
+
+// NewOptions returns new options struct that filled by opts
+func NewOptions(opts ...Option) Options {
+	options := Options{
+		Logger: logger.DefaultLogger,
+		Meter:  meter.DefaultMeter,
+		Tracer: tracer.DefaultTracer,
+	}
+
+	for _, o := range opts {
+		o(&options)
+	}
+
+	return options
+}
+
+// WithEndpoint sets a proxy endpoint
+func WithEndpoint(e string) Option {
+	return func(o *Options) {
+		o.Endpoint = e
+	}
+}
+
+// WithClient sets the client
+func WithClient(c client.Client) Option {
+	return func(o *Options) {
+		o.Client = c
+	}
+}
+
+// WithRouter specifies the router to use
+func WithRouter(r router.Router) Option {
+	return func(o *Options) {
+		o.Router = r
+	}
+}
+
+// WithLogger specifies the logger to use
+func WithLogger(l logger.Logger) Option {
+	return func(o *Options) {
+		o.Logger = l
+	}
+}
+
+// WithMeter specifies the meter to use
+func WithMeter(m meter.Meter) Option {
+	return func(o *Options) {
+		o.Meter = m
+	}
+}
+
+// WithLink sets a link for outbound requests
+func WithLink(name string, c client.Client) Option {
+	return func(o *Options) {
+		if o.Links == nil {
+			o.Links = make(map[string]client.Client)
+		}
+		o.Links[name] = c
+	}
+}
+
+// Tracer to be used for tracing
+func Tracer(t tracer.Tracer) Option {
+	return func(o *Options) {
+		o.Tracer = t
+	}
+}

proxy/proxy.go

@@ -0,0 +1,21 @@
+// Package proxy is a transparent proxy built on the micro/server
+package proxy // import "go.unistack.org/micro/v3/proxy"
+
+import (
+	"context"
+
+	"go.unistack.org/micro/v3/server"
+)
+
+// DefaultEndpoint holds default proxy address
+var DefaultEndpoint = "localhost:9090"
+
+// Proxy can be used as a proxy server for micro services
+type Proxy interface {
+	// ProcessMessage handles inbound messages
+	ProcessMessage(context.Context, server.Message) error
+	// ServeRequest handles inbound requests
+	ServeRequest(context.Context, server.Request, server.Response) error
+	// Name of the proxy protocol
+	String() string
+}

register/extractor.go

@@ -6,7 +6,7 @@ import (
 	"unicode"
 	"unicode/utf8"
 
-	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v3/metadata"
 )
 
 // ExtractValue from reflect.Type from specified depth

register/memory/memory.go

@@ -1,15 +1,13 @@
-package memory
+package register
 
 import (
 	"context"
 	"sync"
 	"time"
 
-	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v4/register"
-
-	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/util/id"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v3/util/id"
 )
 
 var (
@@ -26,16 +24,16 @@ type node struct {
 type record struct {
 	Name      string
 	Version   string
-	Metadata  metadata.Metadata
+	Metadata  map[string]string
 	Nodes     map[string]*node
 	Endpoints []*register.Endpoint
 }
 
 type memory struct {
+	sync.RWMutex
 	records  map[string]services
 	watchers map[string]*watcher
 	opts     register.Options
-	sync.RWMutex
 }
 
 // services is a KV map with service name as the key and a map of records as the value
@@ -66,7 +64,7 @@ func (m *memory) ttlPrune() {
 					for id, n := range record.Nodes {
 						if n.TTL != 0 && time.Since(n.LastSeen) > n.TTL {
 							if m.opts.Logger.V(logger.DebugLevel) {
-								m.opts.Logger.Debug(m.opts.Context, "RegisterTTL expired for node "+n.ID+" of service "+service)
+								m.opts.Logger.Debugf(m.opts.Context, "Register TTL expired for node %s of service %s", n.ID, service)
 							}
 							delete(m.records[domain][service][version].Nodes, id)
 						}
@@ -102,20 +100,10 @@ func (m *memory) sendEvent(r *register.Result) {
 }
 
 func (m *memory) Connect(ctx context.Context) error {
-	select {
-	case <-ctx.Done():
-		return ctx.Err()
-	default:
-	}
 	return nil
 }
 
 func (m *memory) Disconnect(ctx context.Context) error {
-	select {
-	case <-ctx.Done():
-		return ctx.Err()
-	default:
-	}
 	return nil
 }
 
@@ -136,11 +124,6 @@ func (m *memory) Options() register.Options {
 }
 
 func (m *memory) Register(ctx context.Context, s *register.Service, opts ...register.RegisterOption) error {
-	select {
-	case <-ctx.Done():
-		return ctx.Err()
-	default:
-	}
 	m.Lock()
 	defer m.Unlock()
 
@@ -154,11 +137,11 @@ func (m *memory) Register(ctx context.Context, s *register.Service, opts ...regi
 
 	// domain is set in metadata so it can be passed to watchers
 	if s.Metadata == nil {
-		s.Metadata = metadata.New(0)
+		s.Metadata = map[string]string{"domain": options.Domain}
+	} else {
+		s.Metadata["domain"] = options.Domain
 	}
 
-	s.Metadata.Set("domain", options.Domain)
-
 	// ensure the service name exists
 	r := serviceToRecord(s, options.TTL)
 	if _, ok := srvs[s.Name]; !ok {
@@ -168,7 +151,7 @@ func (m *memory) Register(ctx context.Context, s *register.Service, opts ...regi
 	if _, ok := srvs[s.Name][s.Version]; !ok {
 		srvs[s.Name][s.Version] = r
 		if m.opts.Logger.V(logger.DebugLevel) {
-			m.opts.Logger.Debug(m.opts.Context, "register added new service: "+s.Name+", version "+s.Version)
+			m.opts.Logger.Debugf(m.opts.Context, "Register added new service: %s, version: %s", s.Name, s.Version)
 		}
 		m.records[options.Domain] = srvs
 		go m.sendEvent(&register.Result{Action: "create", Service: s})
@@ -182,8 +165,15 @@ func (m *memory) Register(ctx context.Context, s *register.Service, opts ...regi
 			continue
 		}
 
-		metadata := metadata.Copy(n.Metadata)
-		metadata.Set("domain", options.Domain)
+		metadata := make(map[string]string, len(n.Metadata))
+
+		// make copy of metadata
+		for k, v := range n.Metadata {
+			metadata[k] = v
+		}
+
+		// set the domain
+		metadata["domain"] = options.Domain
 
 		// add the node
 		srvs[s.Name][s.Version].Nodes[n.ID] = &node{
@@ -201,14 +191,14 @@ func (m *memory) Register(ctx context.Context, s *register.Service, opts ...regi
 
 	if addedNodes {
 		if m.opts.Logger.V(logger.DebugLevel) {
-			m.opts.Logger.Debug(m.opts.Context, "register added new node to service: "+s.Name+", version "+s.Version)
+			m.opts.Logger.Debugf(m.opts.Context, "Register added new node to service: %s, version: %s", s.Name, s.Version)
 		}
 		go m.sendEvent(&register.Result{Action: "update", Service: s})
 	} else {
 		// refresh TTL and timestamp
 		for _, n := range s.Nodes {
 			if m.opts.Logger.V(logger.DebugLevel) {
-				m.opts.Logger.Debug(m.opts.Context, "updated registration for service: "+s.Name+", version "+s.Version)
+				m.opts.Logger.Debugf(m.opts.Context, "Updated registration for service: %s, version: %s", s.Name, s.Version)
 			}
 			srvs[s.Name][s.Version].Nodes[n.ID].TTL = options.TTL
 			srvs[s.Name][s.Version].Nodes[n.ID].LastSeen = time.Now()
@@ -227,9 +217,10 @@ func (m *memory) Deregister(ctx context.Context, s *register.Service, opts ...re
 
 	// domain is set in metadata so it can be passed to watchers
 	if s.Metadata == nil {
-		s.Metadata = metadata.New(0)
+		s.Metadata = map[string]string{"domain": options.Domain}
+	} else {
+		s.Metadata["domain"] = options.Domain
 	}
-	s.Metadata.Set("domain", options.Domain)
 
 	// if the domain doesn't exist, there is nothing to deregister
 	services, ok := m.records[options.Domain]
@@ -252,7 +243,7 @@ func (m *memory) Deregister(ctx context.Context, s *register.Service, opts ...re
 	for _, n := range s.Nodes {
 		if _, ok := version.Nodes[n.ID]; ok {
 			if m.opts.Logger.V(logger.DebugLevel) {
-				m.opts.Logger.Debug(m.opts.Context, "register removed node from service: "+s.Name+", version "+s.Version)
+				m.opts.Logger.Debugf(m.opts.Context, "Register removed node from service: %s, version: %s", s.Name, s.Version)
 			}
 			delete(version.Nodes, n.ID)
 		}
@@ -273,7 +264,7 @@ func (m *memory) Deregister(ctx context.Context, s *register.Service, opts ...re
 		go m.sendEvent(&register.Result{Action: "delete", Service: s})
 
 		if m.opts.Logger.V(logger.DebugLevel) {
-			m.opts.Logger.Debug(m.opts.Context, "register removed service: "+s.Name)
+			m.opts.Logger.Debugf(m.opts.Context, "Register removed service: %s", s.Name)
 		}
 		return nil
 	}
@@ -282,7 +273,7 @@ func (m *memory) Deregister(ctx context.Context, s *register.Service, opts ...re
 	delete(m.records[options.Domain][s.Name], s.Version)
 	go m.sendEvent(&register.Result{Action: "delete", Service: s})
 	if m.opts.Logger.V(logger.DebugLevel) {
-		m.opts.Logger.Debug(m.opts.Context, "register removed service: "+s.Name+", version "+s.Version)
+		m.opts.Logger.Debugf(m.opts.Context, "Register removed service: %s, version: %s", s.Name, s.Version)
 	}
 
 	return nil
@@ -434,24 +425,16 @@ func (m *watcher) Next() (*register.Result, error) {
 				continue
 			}
 
-			if m.wo.Domain == register.WildcardDomain {
-				return r, nil
-			}
-
-			if r.Service.Metadata == nil {
-				continue
-			}
-
 			// extract domain from service metadata
 			var domain string
-			if v, ok := r.Service.Metadata.Get("domain"); ok && v != "" {
-				domain = v
+			if r.Service.Metadata != nil && len(r.Service.Metadata["domain"]) > 0 {
+				domain = r.Service.Metadata["domain"]
 			} else {
 				domain = register.DefaultDomain
 			}
 
 			// only send the event if watching the wildcard or this specific domain
-			if m.wo.Domain == domain {
+			if m.wo.Domain == register.WildcardDomain || m.wo.Domain == domain {
 				return r, nil
 			}
 		case <-m.exit:
@@ -470,7 +453,10 @@ func (m *watcher) Stop() {
 }
 
 func serviceToRecord(s *register.Service, ttl time.Duration) *record {
-	metadata := metadata.Copy(s.Metadata)
+	metadata := make(map[string]string, len(s.Metadata))
+	for k, v := range s.Metadata {
+		metadata[k] = v
+	}
 
 	nodes := make(map[string]*node, len(s.Nodes))
 	for _, n := range s.Nodes {
@@ -482,7 +468,9 @@ func serviceToRecord(s *register.Service, ttl time.Duration) *record {
 	}
 
 	endpoints := make([]*register.Endpoint, len(s.Endpoints))
-	copy(endpoints, s.Endpoints)
+	for i, e := range s.Endpoints {
+		endpoints[i] = e
+	}
 
 	return &record{
 		Name:      s.Name,
@@ -494,11 +482,20 @@ func serviceToRecord(s *register.Service, ttl time.Duration) *record {
 }
 
 func recordToService(r *record, domain string) *register.Service {
+	metadata := make(map[string]string, len(r.Metadata))
+	for k, v := range r.Metadata {
+		metadata[k] = v
+	}
+
+	// set the domain in metadata so it can be determined when a wildcard query is performed
+	metadata["domain"] = domain
+
 	endpoints := make([]*register.Endpoint, len(r.Endpoints))
 	for i, e := range r.Endpoints {
-		md := metadata.Copy(e.Metadata)
-		// set the domain in metadata so it can be determined when a wildcard query is performed
-		md.Set("domain", domain)
+		md := make(map[string]string, len(e.Metadata))
+		for k, v := range e.Metadata {
+			md[k] = v
+		}
 
 		endpoints[i] = &register.Endpoint{
 			Name:     e.Name,
@@ -511,10 +508,15 @@ func recordToService(r *record, domain string) *register.Service {
 	nodes := make([]*register.Node, len(r.Nodes))
 	i := 0
 	for _, n := range r.Nodes {
+		md := make(map[string]string, len(n.Metadata))
+		for k, v := range n.Metadata {
+			md[k] = v
+		}
+
 		nodes[i] = &register.Node{
 			ID:       n.ID,
 			Address:  n.Address,
-			Metadata: metadata.Copy(n.Metadata),
+			Metadata: md,
 		}
 		i++
 	}
@@ -522,7 +524,7 @@ func recordToService(r *record, domain string) *register.Service {
 	return &register.Service{
 		Name:      r.Name,
 		Version:   r.Version,
-		Metadata:  metadata.Copy(r.Metadata),
+		Metadata:  metadata,
 		Endpoints: endpoints,
 		Nodes:     nodes,
 	}